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  <xs:element id="prph_IssuanceOfSecuredPromissoryNoteReceivable" abstract="false" name="IssuanceOfSecuredPromissoryNoteReceivable" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_FullyReservedTradeReceivablesMember" abstract="true" name="FullyReservedTradeReceivablesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_FinanceLeaseCost" abstract="false" name="FinanceLeaseCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_TypeOfArrangementDomain" abstract="true" name="TypeOfArrangementDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_A2022PlanMember" abstract="true" name="A2022PlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_FinancingAgreementPeriodicPayment" abstract="false" name="FinancingAgreementPeriodicPayment" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_DeferredTaxLiabilitiesDepreciation" abstract="false" name="DeferredTaxLiabilitiesDepreciation" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_FinancingArrangementAggregateRepaymentAmount" abstract="false" name="FinancingArrangementAggregateRepaymentAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_SeptemberTwoThousandAndTwentyNoteMember" abstract="false" name="SeptemberTwoThousandAndTwentyNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_AssetAcquisitionConsiderationTransferredPromissoryNotePayoff" abstract="false" name="AssetAcquisitionConsiderationTransferredPromissoryNotePayoff" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingWeightedAverageExercisePrice1" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsOutstandingWeightedAverageExercisePrice1" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="prph_ContractManufacturingMember" abstract="false" name="ContractManufacturingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_DebtSecuritiesAvailableForSaleMaturityPeriod" abstract="false" name="DebtSecuritiesAvailableForSaleMaturityPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeGrantedWarrantsWeightedAverageRemainingContractualTerm2" abstract="false" name="ShareBasedCompensationSharesAuthorizedUnderStockOptionPlansExercisePriceRangeGrantedWarrantsWeightedAverageRemainingContractualTerm2" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_InsuranceProvidersMember" abstract="false" name="InsuranceProvidersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_GenomicProductsAndServicesMember" abstract="false" name="GenomicProductsAndServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_IncreaseDecreaseInDeferredIncomeTaxLiabilities" abstract="false" name="IncreaseDecreaseInDeferredIncomeTaxLiabilities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_CertainHoldersMember" abstract="true" name="CertainHoldersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_AssetAcquisitionSharesIssuedAndIssuableValuePerShare" abstract="false" name="AssetAcquisitionSharesIssuedAndIssuableValuePerShare" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="prph_A2022DirectorsPlanMember" abstract="true" name="A2022DirectorsPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_CommonStockPurchaseWarrantsMember" abstract="false" name="CommonStockPurchaseWarrantsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_TaxCreditCarryforwardLimitationAmount" abstract="false" name="TaxCreditCarryforwardLimitationAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_InterestOnUnsecuredConvertiblePromissoryNote" abstract="false" name="InterestOnUnsecuredConvertiblePromissoryNote" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_Amended2022DirectorsPlanMember" abstract="true" name="Amended2022DirectorsPlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_LesseeOperatingLeaseAbatementPeriod" abstract="false" name="LesseeOperatingLeaseAbatementPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_ShareBasedPaymentArrangementExpenseReversal" abstract="false" name="ShareBasedPaymentArrangementExpenseReversal" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_IncreaseDecreaseInAccruedDiagnosticServices" abstract="false" name="IncreaseDecreaseInAccruedDiagnosticServices" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_CorporateStockMember" abstract="true" name="CorporateStockMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_WeightedAverageRemainingContractualLifeWarrantsVestedAndExercisable" abstract="false" name="WeightedAverageRemainingContractualLifeWarrantsVestedAndExercisable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_LinebackerLicenseAgreementsMember" abstract="true" name="LinebackerLicenseAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_BlackScholesOptionPricingModelMember" abstract="true" name="BlackScholesOptionPricingModelMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_PurchaseAgreementRoyaltyPercent" abstract="false" name="PurchaseAgreementRoyaltyPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:percentItemType"/>
  <xs:element id="prph_UpfrontLicenseFee" abstract="false" name="UpfrontLicenseFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_DiagnosticServicesClientsTwoMember" abstract="false" name="DiagnosticServicesClientsTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_OldBridgeNewJerseyMember" abstract="false" name="OldBridgeNewJerseyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_RetailAndOtherMember" abstract="false" name="RetailAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_NumberOfInvestors" abstract="false" name="NumberOfInvestors" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_ManufacturingAgreementRenewalOptions" abstract="false" name="ManufacturingAgreementRenewalOptions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_LesseeOperatingLeaseNumberOfRenewalOptions" abstract="false" name="LesseeOperatingLeaseNumberOfRenewalOptions" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_NumberOfSites" abstract="false" name="NumberOfSites" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_NewDrugApplicationMember" abstract="true" name="NewDrugApplicationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_NumberOfLicensedCompounds" abstract="false" name="NumberOfLicensedCompounds" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_AssetAcquisitionConsiderationTransferredLiabilityPayoff" abstract="false" name="AssetAcquisitionConsiderationTransferredLiabilityPayoff" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_LeaseLiability" abstract="false" name="LeaseLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_PaymentsForAssetAcquisition" abstract="false" name="PaymentsForAssetAcquisition" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_DiagnosticServicesMember" abstract="false" name="DiagnosticServicesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_IssuanceOfCommonStockSharesExerciseOfWarrant" abstract="false" name="IssuanceOfCommonStockSharesExerciseOfWarrant" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="prph_ReimbursementReceivableMember" abstract="true" name="ReimbursementReceivableMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_NumberOfDebtInstruments" abstract="false" name="NumberOfDebtInstruments" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_IssuanceOfCommonSharesForDebtConversion" abstract="false" name="IssuanceOfCommonSharesForDebtConversion" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_PhaseThreeMember" abstract="true" name="PhaseThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_NewYorkFirstFloorLeaseMember" abstract="true" name="NewYorkFirstFloorLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_OperatingAndOtherExpenses" abstract="false" name="OperatingAndOtherExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_LicenseAgreementTerm" abstract="false" name="LicenseAgreementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_MrKamalObbadMember" abstract="false" name="MrKamalObbadMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_BESmartLicenseAgreementMember" abstract="true" name="BESmartLicenseAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_NewYorkSecondFloorLeaseMember" abstract="true" name="NewYorkSecondFloorLeaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_LeaseLiabilityToBePaidYearOne" abstract="false" name="LeaseLiabilityToBePaidYearOne" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_InducementOptionAwardMember" abstract="false" name="InducementOptionAwardMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_AdditionalPaymentOfFee" abstract="false" name="AdditionalPaymentOfFee" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_LeaseLiabilityToBePaidYearFour" abstract="false" name="LeaseLiabilityToBePaidYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_IssuanceOfCommonStockUponExerciseOfWarrantAmount" abstract="false" name="IssuanceOfCommonStockUponExerciseOfWarrantAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantedWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_SegmentConcentrationRiskMember" abstract="true" name="SegmentConcentrationRiskMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_LesseeOperatingLeaseOptionToTerminateNoticePeriod" abstract="false" name="LesseeOperatingLeaseOptionToTerminateNoticePeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="prph_LesseeOperatingLeaseMonthlyBaseRent" abstract="false" name="LesseeOperatingLeaseMonthlyBaseRent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_ShareBasedCompensationAwardTrancheFourMember" abstract="true" name="ShareBasedCompensationAwardTrancheFourMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="prph_LeaseLiabilityToBePaidAfterYearFive" abstract="false" name="LeaseLiabilityToBePaidAfterYearFive" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_IncreaseDecreaseInDeferredIncomeTaxAssets" abstract="false" name="IncreaseDecreaseInDeferredIncomeTaxAssets" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_CEOOptionsMember" abstract="false" name="CEOOptionsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:domainItemType"/>
  <xs:element id="prph_ProceedsFromFinancingAgreement" abstract="false" name="ProceedsFromFinancingAgreement" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="prph_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsVestedAndExercisableWeightedAverageExercisePrice1" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionsVestedAndExercisableWeightedAverageExercisePrice1" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types1:perShareItemType"/>
  <xs:element id="prph_NumberOfTestsRecognized" abstract="false" name="NumberOfTestsRecognized" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="prph_NetUnrealizedLossGainInvestmentsInMarketableDebtSecurities" abstract="false" name="NetUnrealizedLossGainInvestmentsInMarketableDebtSecurities" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
