<?xml version="1.0" encoding="US-ASCII" standalone="no"?>
<!--Generated by ThunderDome XBRL - 03:22PM UTC 2024-03-28--><xsd:schema xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:ecd="http://xbrl.sec.gov/ecd/2023" xmlns:country="http://xbrl.sec.gov/country/2023" xmlns:currency="http://xbrl.sec.gov/currency/2023" xmlns:dei="http://xbrl.sec.gov/dei/2023" xmlns:dtr-types="http://www.xbrl.org/dtr/type/2020-01-21" xmlns:exch="http://xbrl.sec.gov/exch/2023" xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:naics="http://xbrl.sec.gov/naics/2023" xmlns:poai="http://www.precisiontherapeutics.com/20231231" xmlns:sic="http://xbrl.sec.gov/sic/2023" xmlns:srt="http://fasb.org/srt/2023" xmlns:srt-types="http://fasb.org/srt-types/2023" xmlns:stpr="http://xbrl.sec.gov/stpr/2023" xmlns:us-gaap="http://fasb.org/us-gaap/2023" xmlns:us-types="http://fasb.org/us-types/2023" xmlns:xbrldt="http://xbrl.org/2005/xbrldt" xmlns:xbrli="http://www.xbrl.org/2003/instance" xmlns:xlink="http://www.w3.org/1999/xlink" attributeFormDefault="unqualified" elementFormDefault="qualified" targetNamespace="http://www.precisiontherapeutics.com/20231231">
  <xsd:import namespace="http://www.xbrl.org/2003/instance" schemaLocation="http://www.xbrl.org/2003/xbrl-instance-2003-12-31.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/naics/2023" schemaLocation="https://xbrl.sec.gov/naics/2023/naics-2023.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/country/2023" schemaLocation="https://xbrl.sec.gov/country/2023/country-2023.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/exch/2023" schemaLocation="https://xbrl.sec.gov/exch/2023/exch-2023.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/dei/2023" schemaLocation="https://xbrl.sec.gov/dei/2023/dei-2023.xsd"/>
  <xsd:import namespace="http://fasb.org/srt/2023" schemaLocation="https://xbrl.fasb.org/srt/2023/elts/srt-2023.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/sic/2023" schemaLocation="https://xbrl.sec.gov/sic/2023/sic-2023.xsd"/>
  <xsd:import namespace="http://fasb.org/us-types/2023" schemaLocation="https://xbrl.fasb.org/us-gaap/2023/elts/us-types-2023.xsd"/>
  <xsd:import namespace="http://xbrl.org/2005/xbrldt" schemaLocation="http://www.xbrl.org/2005/xbrldt-2005.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/stpr/2023" schemaLocation="https://xbrl.sec.gov/stpr/2023/stpr-2023.xsd"/>
  <xsd:import namespace="http://fasb.org/srt-types/2023" schemaLocation="https://xbrl.fasb.org/srt/2023/elts/srt-types-2023.xsd"/>
  <xsd:import namespace="http://fasb.org/us-gaap/2023" schemaLocation="https://xbrl.fasb.org/us-gaap/2023/elts/us-gaap-2023.xsd"/>
  <xsd:import namespace="http://www.xbrl.org/dtr/type/2020-01-21" schemaLocation="https://www.xbrl.org/dtr/type/2020-01-21/types.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/currency/2023" schemaLocation="https://xbrl.sec.gov/currency/2023/currency-2023.xsd"/>
  <xsd:import namespace="http://xbrl.sec.gov/ecd/2023" schemaLocation="https://xbrl.sec.gov/ecd/2023/ecd-2023.xsd"/>
  <xsd:import namespace="http://www.xbrl.org/2009/role/negated" schemaLocation="http://www.xbrl.org/lrr/role/negated-2009-12-16.xsd"/>
  <xsd:annotation>
    <xsd:appinfo>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="poai-20231231_lab.xml" xlink:role="http://www.xbrl.org/2003/role/labelLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="poai-20231231_cal.xml" xlink:role="http://www.xbrl.org/2003/role/calculationLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="poai-20231231_def.xml" xlink:role="http://www.xbrl.org/2003/role/definitionLinkbaseRef" xlink:type="simple"/>
      <link:linkbaseRef xlink:arcrole="http://www.w3.org/1999/xlink/properties/linkbase" xlink:href="poai-20231231_pre.xml" xlink:role="http://www.xbrl.org/2003/role/presentationLinkbaseRef" xlink:type="simple"/>
      <link:roleType id="statement-document-and-entity-information" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-document-and-entity-information">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">000 - Document - Document And Entity Information</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-consolidated-balance-sheets-" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-consolidated-balance-sheets-">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">001 - Statement - Consolidated Balance Sheets</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-consolidated-balance-sheets-parentheticals" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-consolidated-balance-sheets-parentheticals">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">002 - Statement - Consolidated Balance Sheets (Parentheticals)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-consolidated-statements-of-net-loss-" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-consolidated-statements-of-net-loss-">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">003 - Statement - Consolidated Statements of Net Loss</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-consolidated-statements-of-stockholders-equity" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-consolidated-statements-of-stockholders-equity">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">004 - Statement - Consolidated Statements of Stockholders' Equity</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-consolidated-statements-of-cash-flows" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-consolidated-statements-of-cash-flows">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">005 - Statement - Consolidated Statements of Cash Flows</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-1-summary-of-significant-accounting-policies" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-1-summary-of-significant-accounting-policies">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995451 - Disclosure - Note 1 - Summary of Significant Accounting Policies</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-2-fair-value-measurements" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-2-fair-value-measurements">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995452 - Disclosure - Note 2 - Fair Value Measurements</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-3-inventories" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-3-inventories">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995453 - Disclosure - Note 3 - Inventories</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-4-property-and-equipment" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-4-property-and-equipment">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995454 - Disclosure - Note 4 - Property and Equipment</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-5-intangible-assets" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-5-intangible-assets">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995455 - Disclosure - Note 5 - Intangible Assets</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-6-leases" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-6-leases">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995456 - Disclosure - Note 6 - Leases</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-7-notes-payable" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-7-notes-payable">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995457 - Disclosure - Note 7 - Notes Payable</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-8-derivatives-" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-8-derivatives-">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995458 - Disclosure - Note 8 - Derivatives</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995459 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-10-income-taxes" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-10-income-taxes">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995460 - Disclosure - Note 10 - Income Taxes</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-11-collaborative-agreement-" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-11-collaborative-agreement-">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995461 - Disclosure - Note 11 - Collaborative Agreement</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-12-retirement-savings-plans" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-12-retirement-savings-plans">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995462 - Disclosure - Note 12 - Retirement Savings Plans</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-13-loss-per-share" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-13-loss-per-share">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995463 - Disclosure - Note 13 - Loss Per Share</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-14-segments" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-14-segments">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995464 - Disclosure - Note 14 - Segments</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-15-subsequent-events" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-15-subsequent-events">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995465 - Disclosure - Note 15 - Subsequent Events</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-significant-accounting-policies-policies" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-significant-accounting-policies-policies">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995466 - Disclosure - Significant Accounting Policies (Policies)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-1-summary-of-significant-accounting-policies-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-1-summary-of-significant-accounting-policies-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995467 - Disclosure - Note 1 - Summary of Significant Accounting Policies (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-2-fair-value-measurements-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-2-fair-value-measurements-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995468 - Disclosure - Note 2 - Fair Value Measurements (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-3-inventories-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-3-inventories-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995469 - Disclosure - Note 3 - Inventories (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-4-property-and-equipment-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-4-property-and-equipment-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995470 - Disclosure - Note 4 - Property and Equipment (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-5-intangible-assets-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-5-intangible-assets-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995471 - Disclosure - Note 5 - Intangible Assets (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-6-leases-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-6-leases-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995472 - Disclosure - Note 6 - Leases (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-8-derivatives-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-8-derivatives-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995473 - Disclosure - Note 8 - Derivatives (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995474 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-10-income-taxes-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-10-income-taxes-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995475 - Disclosure - Note 10 - Income Taxes (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-13-loss-per-share-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-13-loss-per-share-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995476 - Disclosure - Note 13 - Loss Per Share (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-14-segments-tables" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-14-segments-tables">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995477 - Disclosure - Note 14 - Segments (Tables)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-1-summary-of-significant-accounting-policies-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-1-summary-of-significant-accounting-policies-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995478 - Disclosure - Note 1 - Summary of Significant Accounting Policies (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-1-summary-of-significant-accounting-policies-property-plant-and-equipment-useful-life-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-1-summary-of-significant-accounting-policies-property-plant-and-equipment-useful-life-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995479 - Disclosure - Note 1 - Summary of Significant Accounting Policies - Property, Plant and Equipment Useful Life (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-2-fair-value-measurements-fair-value-assets-measured-on-recurring-basis-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-2-fair-value-measurements-fair-value-assets-measured-on-recurring-basis-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995480 - Disclosure - Note 2 - Fair Value Measurements - Fair Value, Assets Measured on Recurring Basis (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-3-inventories-schedule-of-inventory-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-3-inventories-schedule-of-inventory-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995481 - Disclosure - Note 3 - Inventories - Schedule of Inventory (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-4-property-and-equipment-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-4-property-and-equipment-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995482 - Disclosure - Note 4 - Property and Equipment (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-4-property-and-equipment-schedule-of-property-plant-and-equipment-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-4-property-and-equipment-schedule-of-property-plant-and-equipment-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995483 - Disclosure - Note 4 - Property and Equipment - Schedule of Property, Plant and Equipment (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-5-intangible-assets-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-5-intangible-assets-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995484 - Disclosure - Note 5 - Intangible Assets (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-5-intangible-assets-components-of-intangible-assets-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-5-intangible-assets-components-of-intangible-assets-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995485 - Disclosure - Note 5 - Intangible Assets - Components of Intangible Assets (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-5-intangible-assets-estimated-future-amortization-expense-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-5-intangible-assets-estimated-future-amortization-expense-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995486 - Disclosure - Note 5 - Intangible Assets - Estimated Future Amortization Expense (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-5-intangible-assets-goodwill-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-5-intangible-assets-goodwill-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995487 - Disclosure - Note 5 - Intangible Assets - Goodwill (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-6-leases-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-6-leases-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995488 - Disclosure - Note 6 - Leases (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-6-leases-lease-information-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-6-leases-lease-information-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995489 - Disclosure - Note 6 - Leases - Lease Information (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-6-leases-rent-obligation-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-6-leases-rent-obligation-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995490 - Disclosure - Note 6 - Leases - Rent Obligation (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-7-notes-payable-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-7-notes-payable-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995491 - Disclosure - Note 7 - Notes Payable (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-8-derivatives-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-8-derivatives-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995492 - Disclosure - Note 8 - Derivatives (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-8-derivatives-change-in-fair-value-of-derivative-liabilities-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-8-derivatives-change-in-fair-value-of-derivative-liabilities-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995493 - Disclosure - Note 8 - Derivatives - Change in Fair Value of Derivative Liabilities (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995494 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants-stock-offerings-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants-stock-offerings-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995495 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants - Stock Offerings (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995496 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants - Summary of Transactions for Stock Options and Warrants (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995497 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants - Summary of Status of Options and Warrants Outstanding (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-9-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-9-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995498 - Disclosure - Note 9 - Stockholders' Equity, Stock Options and Warrants - Schedule of Listing of Stock Options and Warrants (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-10-income-taxes-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-10-income-taxes-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995499 - Disclosure - Note 10 - Income Taxes (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-10-income-taxes-reconciliation-of-income-tax-benefit-expense-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-10-income-taxes-reconciliation-of-income-tax-benefit-expense-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995500 - Disclosure - Note 10 - Income Taxes - Reconciliation of Income Tax Benefit (Expense) (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-10-income-taxes-components-of-deferred-income-taxes-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-10-income-taxes-components-of-deferred-income-taxes-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995501 - Disclosure - Note 10 - Income Taxes - Components of Deferred Income Taxes (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-12-retirement-savings-plans-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-12-retirement-savings-plans-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995502 - Disclosure - Note 12 - Retirement Savings Plans (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-13-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-13-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995503 - Disclosure - Note 13 - Loss Per Share - Shares Used in Basic and Diluted Loss Per Common Share Computations (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-13-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-13-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995504 - Disclosure - Note 13 - Loss Per Share - Antidilutive Securities Excluded from the Diluted Calculations (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-14-segments-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-14-segments-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995505 - Disclosure - Note 14 - Segments (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-14-segments-segments-details" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-14-segments-segments-details">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995506 - Disclosure - Note 14 - Segments - Segments (Details)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
      <link:roleType id="statement-note-15-subsequent-events-details-textual" roleURI="http://www.precisiontherapeutics.com/20231231/role/statement-note-15-subsequent-events-details-textual">
        <link:definition xmlns="http://www.xbrl.org/2003/linkbase">995507 - Disclosure - Note 15 - Subsequent Events (Details Textual)</link:definition>
        <link:usedOn>link:calculationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
        <link:usedOn>link:presentationLink</link:usedOn>
      </link:roleType>
    </xsd:appinfo>
  </xsd:annotation>
  <xsd:element id="poai_AccumulatedImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill" name="AccumulatedImpairmentOfIntangibleAssetsIndefinitelivedExcludingGoodwill" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_AgentWarrantsInConnectionWithJune2020WarrantMember" name="AgentWarrantsInConnectionWithJune2020WarrantMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_AgentWarrantsInConnectionWithMarch2020PrivatePlacementMember" name="AgentWarrantsInConnectionWithMarch2020PrivatePlacementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_AgentWarrantsIssuedInConnectionWithMay2020OfferingMember" name="AgentWarrantsIssuedInConnectionWithMay2020OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BirminghamMember" name="BirminghamMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_BirminghamOperatingSegmentMember" name="BirminghamOperatingSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ChangeInDeferredTaxAssetsAttributableToOperatingLosses" name="ChangeInDeferredTaxAssetsAttributableToOperatingLosses" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_ChangeInOperatingLossCarryforwards" name="ChangeInOperatingLossCarryforwards" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightCancelledDuringPeriod" name="ClassOfWarrantOrRightCancelledDuringPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightCancelledDuringPeriodExercisePrice" name="ClassOfWarrantOrRightCancelledDuringPeriodExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsPercentOfStockPrice" name="ClassOfWarrantOrRightExercisePriceOfWarrantsOrRightsPercentOfStockPrice" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ClassOfWarrantOrRightExpiredDuringPeriod" name="ClassOfWarrantOrRightExpiredDuringPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightExpiredDuringPeriodExercisePrice" name="ClassOfWarrantOrRightExpiredDuringPeriodExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightForfeitedDuringPeriod" name="ClassOfWarrantOrRightForfeitedDuringPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightIssuedDuringPeriod" name="ClassOfWarrantOrRightIssuedDuringPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightIssuedDuringPeriodExercisePrice" name="ClassOfWarrantOrRightIssuedDuringPeriodExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ClassOfWarrantOrRightNumberOfWarrantsVestedAndExercisable" name="ClassOfWarrantOrRightNumberOfWarrantsVestedAndExercisable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ClassOfWarrantOrRightOutstandingWeightedAverageRemainingContractualTerm" name="ClassOfWarrantOrRightOutstandingWeightedAverageRemainingContractualTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_CorporateOfficeInPittsburghMember" name="CorporateOfficeInPittsburghMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_DeferredTaxAssetsCapitalizedRD" name="DeferredTaxAssetsCapitalizedRD" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsDepreciation" name="DeferredTaxAssetsDepreciation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsLeaseLiabilities" name="DeferredTaxAssetsLeaseLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsLiabilitiesGross" name="DeferredTaxAssetsLiabilitiesGross" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsNQSOCompensation" name="DeferredTaxAssetsNQSOCompensation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DeferredTaxAssetsOperatingLossCarryforwardsAndCredits" name="DeferredTaxAssetsOperatingLossCarryforwardsAndCredits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="poai_DefinedContributionPlanEmployerContributionAmount" name="DefinedContributionPlanEmployerContributionAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DemoEquipmentMember" name="DemoEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_DocumentAndEntityInformation" name="DocumentAndEntityInformation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_EaganMember" name="EaganMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_EaganMinnesotaOfficeMember" name="EaganMinnesotaOfficeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationForeignIncomeTaxBenefitAmount" name="EffectiveIncomeTaxRateReconciliationForeignIncomeTaxBenefitAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationStateNetOperatingLossAdjustmentAmount" name="EffectiveIncomeTaxRateReconciliationStateNetOperatingLossAdjustmentAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_EffectiveIncomeTaxRateReconciliationStateTaxRateAdjustmentAmount" name="EffectiveIncomeTaxRateReconciliationStateTaxRateAdjustmentAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_EquityIncentivePlanMember" name="EquityIncentivePlanMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_EquityInstrumentsIssuedForManagementAndConsulting" name="EquityInstrumentsIssuedForManagementAndConsulting" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_EquityLinePurchaseAgreementMember" name="EquityLinePurchaseAgreementMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ExistingWarrantsMember" name="ExistingWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_GainLossesOnDebtRevaluation" name="GainLossesOnDebtRevaluation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_IssuanceOrSaleOfEquityCanBeRaised" name="IssuanceOrSaleOfEquityCanBeRaised" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_LaboratoryEquipmentMember" name="LaboratoryEquipmentMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_ManufacturingToolingMember" name="ManufacturingToolingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_MaximumExpensesReimbursableToPlacementAgent" name="MaximumExpensesReimbursableToPlacementAgent" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2022FirstOfferingMember" name="May2022FirstOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2022OfferingsMember" name="May2022OfferingsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_May2022SecondOfferingMember" name="May2022SecondOfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_MeasurementInputExpectedCashFlowTermMember" name="MeasurementInputExpectedCashFlowTermMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_NatureOfOperationsAndGoingConcernPolicyPolicyTextBlock" name="NatureOfOperationsAndGoingConcernPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_NumberOfTumorSamples" name="NumberOfTumorSamples" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_OneIndividualMember" name="OneIndividualMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PatentsAndTrademarksMember" name="PatentsAndTrademarksMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PittsburghMember" name="PittsburghMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_PlacementAgentWarrantsMember" name="PlacementAgentWarrantsMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PreferredStockConversionRate" name="PreferredStockConversionRate" nillable="true" substitutionGroup="xbrli:item" type="xbrli:pureItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PreferredStockDividendsSharesPerShare" name="PreferredStockDividendsSharesPerShare" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_PreferredStockVotingRightsPerShare" name="PreferredStockVotingRightsPerShare" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ProceedsFromIssuanceOfStockPursuantToEquityLine" name="ProceedsFromIssuanceOfStockPursuantToEquityLine" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="poai_PropertyPlantAndEquipmentUsefulLifeTableTextBlock" name="PropertyPlantAndEquipmentUsefulLifeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_ReportingUnitMeasurementInput" name="ReportingUnitMeasurementInput" nillable="true" substitutionGroup="xbrli:item" type="xbrli:decimalItemType" xbrli:periodType="instant"/>
  <xsd:element abstract="true" id="poai_ReverseStockSplitMember" name="ReverseStockSplitMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SaleOfStockAgentPlacementFeePercentOfGrossProceeds" name="SaleOfStockAgentPlacementFeePercentOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockManagementFeePercentOfGrossProceeds" name="SaleOfStockManagementFeePercentOfGrossProceeds" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_SaleOfStockPlacementAgentWarrantsAssignedNumberOfSecuritiesCalledByWarrantsPercentOfSharesSold" name="SaleOfStockPlacementAgentWarrantsAssignedNumberOfSecuritiesCalledByWarrantsPercentOfSharesSold" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:percentItemType" xbrli:periodType="instant"/>
  <xsd:element id="poai_ScheduleOfSharebasedCompensationSharesAuthorizedUnderStockOptionAndWarrantPlansByExercisePriceRangeTableTextBlock" name="ScheduleOfSharebasedCompensationSharesAuthorizedUnderStockOptionAndWarrantPlansByExercisePriceRangeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_SeriesBConvertiblePreferredStockMember" name="SeriesBConvertiblePreferredStockMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice" name="SharebasedCompensationArrangementsBySharebasedPaymentAwardOptionsCancelledInPeriodWeightedAverageExercisePrice" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockIncentivePlan2012Member" name="StockIncentivePlan2012Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesAccruedInterest" name="StockIssuedDuringPeriodSharesAccruedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesInducementToEquityLine" name="StockIssuedDuringPeriodSharesInducementToEquityLine" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodSharesIssuedForServicesAndOtherAdjustments" name="StockIssuedDuringPeriodSharesIssuedForServicesAndOtherAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:sharesItemType" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueAccruedInterest" name="StockIssuedDuringPeriodValueAccruedInterest" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueInducementToEquityLine" name="StockIssuedDuringPeriodValueInducementToEquityLine" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueIssuedForServicesAndOtherAdjustments" name="StockIssuedDuringPeriodValueIssuedForServicesAndOtherAdjustments" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="poai_StockIssuedDuringPeriodValueReverseStockSplits" name="StockIssuedDuringPeriodValueReverseStockSplits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2014Member" name="StockOptions2014Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2015Member" name="StockOptions2015Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2016Member" name="StockOptions2016Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2017Member" name="StockOptions2017Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2018Member" name="StockOptions2018Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2019Member" name="StockOptions2019Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2020Member" name="StockOptions2020Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2021Member" name="StockOptions2021Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2022Member" name="StockOptions2022Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptions2023Member" name="StockOptions2023Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsFourMember" name="StockOptionsFourMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsOneMember" name="StockOptionsOneMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsThreeMember" name="StockOptionsThreeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_StockOptionsTwoMember" name="StockOptionsTwoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_TradeNames1Member" name="TradeNames1Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantFourMember" name="WarrantFourMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantOneMember" name="WarrantOneMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantThreeMember" name="WarrantThreeMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantTwoMember" name="WarrantTwoMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2019Member" name="Warrants2019Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2020Member" name="Warrants2020Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2021Member" name="Warrants2021Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_Warrants2022Member" name="Warrants2022Member" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_WarrantsIssuedWithFirstMay2022OfferingMember" name="WarrantsIssuedWithFirstMay2022OfferingMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_ZPREDICTAMember" name="ZPREDICTAMember" nillable="true" substitutionGroup="xbrli:item" type="dtr-types:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-1-summary-of-significant-accounting-policies-property-plant-and-equipment-useful-life-details" name="statement-statement-note-1-summary-of-significant-accounting-policies-property-plant-and-equipment-useful-life-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-1-summary-of-significant-accounting-policies-tables" name="statement-statement-note-1-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-10-income-taxes-components-of-deferred-income-taxes-details" name="statement-statement-note-10-income-taxes-components-of-deferred-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-10-income-taxes-reconciliation-of-income-tax-benefit-expense-details" name="statement-statement-note-10-income-taxes-reconciliation-of-income-tax-benefit-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-10-income-taxes-tables" name="statement-statement-note-10-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-13-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details" name="statement-statement-note-13-loss-per-share-antidilutive-securities-excluded-from-the-diluted-calculations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-13-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details" name="statement-statement-note-13-loss-per-share-shares-used-in-basic-and-diluted-loss-per-common-share-computations-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-13-loss-per-share-tables" name="statement-statement-note-13-loss-per-share-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-14-segments-segments-details" name="statement-statement-note-14-segments-segments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-14-segments-segments-details3021BBE8-8276-46B5-A89E-367D21E32056" name="statement-statement-note-14-segments-segments-details3021BBE8-8276-46B5-A89E-367D21E32056" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-14-segments-segments-details61C6A313-ACA4-41A3-A48C-2B94041FF64A" name="statement-statement-note-14-segments-segments-details61C6A313-ACA4-41A3-A48C-2B94041FF64A" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-14-segments-segments-detailsC7E8760A-F7BD-423A-845C-2591DA8241A4" name="statement-statement-note-14-segments-segments-detailsC7E8760A-F7BD-423A-845C-2591DA8241A4" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-14-segments-tables" name="statement-statement-note-14-segments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-fair-value-measurements-fair-value-assets-measured-on-recurring-basis-details" name="statement-statement-note-2-fair-value-measurements-fair-value-assets-measured-on-recurring-basis-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-fair-value-measurements-fair-value-assets-measured-on-recurring-basis-details1FD59F95-A620-4F7F-AB4F-19AB69500A29" name="statement-statement-note-2-fair-value-measurements-fair-value-assets-measured-on-recurring-basis-details1FD59F95-A620-4F7F-AB4F-19AB69500A29" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-2-fair-value-measurements-tables" name="statement-statement-note-2-fair-value-measurements-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-3-inventories-schedule-of-inventory-details" name="statement-statement-note-3-inventories-schedule-of-inventory-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-3-inventories-tables" name="statement-statement-note-3-inventories-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-property-and-equipment-schedule-of-property-plant-and-equipment-details" name="statement-statement-note-4-property-and-equipment-schedule-of-property-plant-and-equipment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-4-property-and-equipment-tables" name="statement-statement-note-4-property-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-intangible-assets-components-of-intangible-assets-details" name="statement-statement-note-5-intangible-assets-components-of-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-intangible-assets-estimated-future-amortization-expense-details" name="statement-statement-note-5-intangible-assets-estimated-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-intangible-assets-goodwill-details" name="statement-statement-note-5-intangible-assets-goodwill-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-5-intangible-assets-tables" name="statement-statement-note-5-intangible-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-6-leases-lease-information-details" name="statement-statement-note-6-leases-lease-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-6-leases-rent-obligation-details" name="statement-statement-note-6-leases-rent-obligation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-6-leases-tables" name="statement-statement-note-6-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-derivatives-change-in-fair-value-of-derivative-liabilities-details" name="statement-statement-note-8-derivatives-change-in-fair-value-of-derivative-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-8-derivatives-tables" name="statement-statement-note-8-derivatives-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details" name="statement-statement-note-9-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details5CC9C404-0EBF-4A0C-804B-503CC7FA5AC4" name="statement-statement-note-9-stockholders-equity-stock-options-and-warrants-schedule-of-listing-of-stock-options-and-warrants-details5CC9C404-0EBF-4A0C-804B-503CC7FA5AC4" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-stockholders-equity-stock-options-and-warrants-stock-offerings-details" name="statement-statement-note-9-stockholders-equity-stock-options-and-warrants-stock-offerings-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details" name="statement-statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-status-of-options-and-warrants-outstanding-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details" name="statement-statement-note-9-stockholders-equity-stock-options-and-warrants-summary-of-transactions-for-stock-options-and-warrants-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-note-9-stockholders-equity-stock-options-and-warrants-tables" name="statement-statement-note-9-stockholders-equity-stock-options-and-warrants-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="poai_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
