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  <xsd:element name="ConversionOfSeriesBPreferredStockToCommonStock" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_ConversionOfSeriesBPreferredStockToCommonStock" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodValueOfSynBiomicsStock" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_StockIssuedDuringPeriodValueOfSynBiomicsStock" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <xsd:element name="ConversionOfSeriesBPreferredStockToCommonStockShares" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_ConversionOfSeriesBPreferredStockToCommonStockShares" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_IncreaseDecreaseLeaseLiability" name="IncreaseDecreaseLeaseLiability" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_IncreaseDecreaseRightOfUseAssets" name="IncreaseDecreaseRightOfUseAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_DeemedDividendsWithBeneficialConversionFeature" name="DeemedDividendsWithBeneficialConversionFeature" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element name="StockWarrantsAbstract" type="xbrli:stringItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_StockWarrantsAbstract" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_AccruedExpensesTableTextBlock" name="AccruedExpensesTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_AccruedEmployeeBenefitsTableTextBlock" name="AccruedEmployeeBenefitsTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_ScheduleOfWarrantActivityTableTextBlock" name="ScheduleOfWarrantActivityTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_ScheduleOfWarrantOutstandingAndExercisableTableTextBlock" name="ScheduleOfWarrantOutstandingAndExercisableTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_PrepaidClinicalResearchOrganizationsExpenseCurrent" name="PrepaidClinicalResearchOrganizationsExpenseCurrent" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_PrepaidConsultingSubscriptionsAndOtherExpenses" name="PrepaidConsultingSubscriptionsAndOtherExpenses" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element name="ComputersAndOfficeEquipmentMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_ComputersAndOfficeEquipmentMember" substitutionGroup="xbrli:item" />
  <xsd:element name="AccruedManufacturingCosts" type="xbrli:monetaryItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="syn_AccruedManufacturingCosts" substitutionGroup="xbrli:item" xbrli:balance="credit" />
  <xsd:element id="syn_AccruedClinicalConsultingServices" name="AccruedClinicalConsultingServices" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="syn_AccruedVendorPayments" name="AccruedVendorPayments" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="syn_ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionExercisePrice" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardFairValueAssumptionExercisePrice" nillable="true" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGrantDateFairValue" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriodGrantDateFairValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element name="StockPlan2007Member" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_StockPlan2007Member" substitutionGroup="xbrli:item" />
  <xsd:element name="StockPlan2010Member" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_StockPlan2010Member" substitutionGroup="xbrli:item" />
  <xsd:element name="GeneralAndAdministrativeExpensesAndResearchAndDevelopmentExpenseMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_GeneralAndAdministrativeExpensesAndResearchAndDevelopmentExpenseMember" substitutionGroup="xbrli:item" />
  <xsd:element name="StockWarrantsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_StockWarrantsMember" substitutionGroup="xbrli:item" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsExercisesInPeriod" type="xbrli:sharesItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOtherThanOptionsExercisesInPeriod" substitutionGroup="xbrli:item" />
  <xsd:element name="ExercisePrice1820Member" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_ExercisePrice1820Member" substitutionGroup="xbrli:item" />
  <xsd:element name="WarrantsExercisePrice" type="dtr-types:perShareItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_WarrantsExercisePrice" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWarrantsExercisableNumber" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsWarrantsExercisableNumber" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element name="OctoberTwoThousandEighteenWarrantsMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_OctoberTwoThousandEighteenWarrantsMember" substitutionGroup="xbrli:item" />
  <xsd:element name="UnderwrittenPublicOfferingMember" type="dtr-types:domainItemType" abstract="true" xbrli:periodType="duration" nillable="true" id="syn_UnderwrittenPublicOfferingMember" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_WarrantTerm" name="WarrantTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_PreferredStockConversionPricePerShare" name="PreferredStockConversionPricePerShare" nillable="true" type="dtr-types:perShareItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="syn_NumberOfCommonStockToBeIssued" name="NumberOfCommonStockToBeIssued" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="syn_AdditionalNumberOfCommonStockToBeIssued" name="AdditionalNumberOfCommonStockToBeIssued" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="syn_NumberOfCommonStockToBeHeldByRelatedParty" name="NumberOfCommonStockToBeHeldByRelatedParty" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="syn_FairValueOfSharesIssued" name="FairValueOfSharesIssued" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element name="BrokerageCommissionPercentage" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="instant" nillable="true" id="syn_BrokerageCommissionPercentage" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_IssueOfWarrantsToPurchaseCommonStock" name="IssueOfWarrantsToPurchaseCommonStock" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element name="InvestmentWarrantsExpirationDate1" type="xbrli:dateItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_InvestmentWarrantsExpirationDate1" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_PreferredStockSharesConverted" name="PreferredStockSharesConverted" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="PercentageOfIssueOfThePublicOffering" type="dtr-types:percentItemType" abstract="false" xbrli:periodType="duration" nillable="true" id="syn_PercentageOfIssueOfThePublicOffering" substitutionGroup="xbrli:item" />
  <xsd:element id="syn_StockIssuedDuringPeriodAtMarketOfferingValue" name="StockIssuedDuringPeriodAtMarketOfferingValue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="syn_StockIssuedDuringPeriodAtMarketOfferingShare" name="StockIssuedDuringPeriodAtMarketOfferingShare" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_BalanceSheetInformationAbstract" name="BalanceSheetInformationAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_ProceedsFromIssuanceAtmOfferingNetOfIssuanceCosts" name="ProceedsFromIssuanceAtmOfferingNetOfIssuanceCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_PrepaidManufacturingExpense" name="PrepaidManufacturingExpense" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_ClinicalTrialAgreementMember" name="ClinicalTrialAgreementMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_EstimatedResearchCosts" name="EstimatedResearchCosts" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_SubsidiaryStockIssuesToVendor" name="SubsidiaryStockIssuesToVendor" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_DisclosureOfLicenseCollaborativeAndEmploymentAgreementsAndCommitmentsAbstract" name="DisclosureOfLicenseCollaborativeAndEmploymentAgreementsAndCommitmentsAbstract" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_LicenseCollaborativeAndEmploymentAgreementsAndCommitmentsTextBlock" name="LicenseCollaborativeAndEmploymentAgreementsAndCommitmentsTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_NoncontrollingInterestPolicyTextBlock" name="NoncontrollingInterestPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_RisksAndUncertaintiesPolicyTextBlock" name="RisksAndUncertaintiesPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_StockBasedPaymentArrangementsPolicyTextBlock" name="StockBasedPaymentArrangementsPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_EstimatedUsefulLifeOfAssetTableTextBlock" name="EstimatedUsefulLifeOfAssetTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_SummaryOfSignificantAccountingPoliciesTable" name="SummaryOfSignificantAccountingPoliciesTable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_SYNBiomicsMember" name="SYNBiomicsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_MoneyMarketAccountsMember" name="MoneyMarketAccountsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_SeriesAAndSeriesBPreferredStockMember" name="SeriesAAndSeriesBPreferredStockMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_SummaryOfSignificantAccountingPoliciesLineItems" name="SummaryOfSignificantAccountingPoliciesLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_RangeOfExercisePrice0004000Member" name="RangeOfExercisePrice0004000Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_RangeOfExercisePrice41007000Member" name="RangeOfExercisePrice41007000Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_RangeOfExercisePrice710010200Member" name="RangeOfExercisePrice710010200Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_SeriesWarrantsMember" name="SeriesWarrantsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_SeriesBWarrantsMember" name="SeriesBWarrantsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_ProceedsFromIssuanceOfCommonStockForExclusiveChannelCollaborationAgreement" name="ProceedsFromIssuanceOfCommonStockForExclusiveChannelCollaborationAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_DrPimentelsMember" name="DrPimentelsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_LicenseCollaborativeAndEmploymentAgreementsAndCommitmentsTable" name="LicenseCollaborativeAndEmploymentAgreementsAndCommitmentsTable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_QuarterlyInstallmentsPaymentPeriodAxis" name="QuarterlyInstallmentsPaymentPeriodAxis" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:dimensionItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_QuarterlyInstallmentsPaymentPeriodDomain" name="QuarterlyInstallmentsPaymentPeriodDomain" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_FirstYearMember" name="FirstYearMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_SecondYearMember" name="SecondYearMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_ThirdYearMember" name="ThirdYearMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_PhaseIClinicalTrialsMember" name="PhaseIClinicalTrialsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_PhaseIiiClinicalTrialsMember" name="PhaseIiiClinicalTrialsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_NdaSubmissionInUsMember" name="NdaSubmissionInUsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_EuropeanMedicinesAgencyApprovalMember" name="EuropeanMedicinesAgencyApprovalMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_RegulatoryApprovalInAsianCountryMember" name="RegulatoryApprovalInAsianCountryMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_PrevAbrLlcMember" name="PrevAbrLlcMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_StevenAShallcrossMember" name="StevenAShallcrossMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_LicenseCollaborativeAndEmploymentAgreementsAndCommitmentsLineItems" name="LicenseCollaborativeAndEmploymentAgreementsAndCommitmentsLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_ResearchAgreementFixedFee" name="ResearchAgreementFixedFee" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element id="syn_MilestonePayment" name="MilestonePayment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_AdditionalCashPaymentForLicenseAgreement" name="AdditionalCashPaymentForLicenseAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_UnregisteredSharesIssuedToLicenseAgreement" name="UnregisteredSharesIssuedToLicenseAgreement" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_AdditionalConsiderationPayable" name="AdditionalConsiderationPayable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_OptionsToBeReceivedCommonStockShares" name="OptionsToBeReceivedCommonStockShares" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_DeferredTaxAssetsStocksIssuedForServices" name="DeferredTaxAssetsStocksIssuedForServices" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_DeferredTaxAssetsStockIssuedForAcquisitionOfProgram" name="DeferredTaxAssetsStockIssuedForAcquisitionOfProgram" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_DeferredTaxAssetsStockIssuedForlicenseAgreement" name="DeferredTaxAssetsStockIssuedForlicenseAgreement" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_DeferredTaxAssetsStockIssuedForMilestonePayment" name="DeferredTaxAssetsStockIssuedForMilestonePayment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_DeferredTaxAssetsTaxDeferredExpenseAmortizableLicenseFee" name="DeferredTaxAssetsTaxDeferredExpenseAmortizableLicenseFee" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_IncomeTaxesTable" name="IncomeTaxesTable" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_IncomeTaxLineItems" name="IncomeTaxLineItems" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_OperatingLossCarryforwardsExpireDate" name="OperatingLossCarryforwardsExpireDate" nillable="true" type="xbrli:stringItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_SyntheticBiomicsIncMember" name="SyntheticBiomicsIncMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_CedarssinaiMedicalCenterMember" name="CedarssinaiMedicalCenterMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_StockPurchaseAgreementMember" name="StockPurchaseAgreementMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_LicenseAgreementAnnualPaymentsDue" name="LicenseAgreementAnnualPaymentsDue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="syn_LicenseAgreementFinalPaymentDue" name="LicenseAgreementFinalPaymentDue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="syn_ShareBasedPaymentArrangementEmployeeAndConsultantMember" name="ShareBasedPaymentArrangementEmployeeAndConsultantMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndWarrantsVestedAndExpectedToVestOutstandingAndExercisableTableTextBlock" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsAndWarrantsVestedAndExpectedToVestOutstandingAndExercisableTableTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_CostOfLivingAdjustmentsPercentage" name="CostOfLivingAdjustmentsPercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_NonCashAdditionOfRightOfUseAssets" name="NonCashAdditionOfRightOfUseAssets" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_EmployeesAndDirectorsMember" name="EmployeesAndDirectorsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_ConsultantMember" name="ConsultantMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_AccretionOfPreferredStockDeemedDividend" name="AccretionOfPreferredStockDeemedDividend" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_FbrCapitalMarketsCoMember" name="FbrCapitalMarketsCoMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_StockPlan2020Member" name="StockPlan2020Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_OperatingLossCarryforwardsLimitationOnUse" name="OperatingLossCarryforwardsLimitationOnUse" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="syn_BeneficialOwnershipPercentage" name="BeneficialOwnershipPercentage" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" />
  <xsd:element id="syn_WarrantExercisePriceAdjustment" name="WarrantExercisePriceAdjustment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_ExercisePrice0.69Member" name="ExercisePrice0.69Member" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="syn_Conversionofseriesapreferredstocktocommonstockshares" name="Conversionofseriesapreferredstocktocommonstockshares" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_Conversionofseriesbpreferredstocktocommonstock" name="Conversionofseriesbpreferredstocktocommonstock" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="syn_PreferredStockPriceAdjustment" name="PreferredStockPriceAdjustment" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_StockIssuedDuringPeriodValueWarrantsExercised" name="StockIssuedDuringPeriodValueWarrantsExercised" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="syn_StockIssuedDuringPeriodSharesWarrantsExercised" name="StockIssuedDuringPeriodSharesWarrantsExercised" nillable="true" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_AdjustmentsToEffectOfPreferredStockPrice" name="AdjustmentsToEffectOfPreferredStockPrice" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="syn_EstimatedFairValueOfInducementConsideration" name="EstimatedFairValueOfInducementConsideration" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="debit" />
  <xsd:element id="syn_NumberOfSharesPurchase" name="NumberOfSharesPurchase" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="syn_NumberOfShareSold" name="NumberOfShareSold" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element name="ExercisePrice0.69TwoMember" id="syn_ExercisePrice0.69TwoMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="Dr.SlimanMember" id="syn_Dr.SlimanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ReturnOfSynBiomicsStock" id="syn_ReturnOfSynBiomicsStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LesseeOperatingLeaseLiabilityPaymentsDueYearSix" id="syn_LesseeOperatingLeaseLiabilityPaymentsDueYearSix" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AdjustmentsToEffectOfWarrantExercisePrice" id="syn_AdjustmentsToEffectOfWarrantExercisePrice" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ConsiderationPurchasePaid" id="syn_ConsiderationPurchasePaid" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="NewTechnologiesMember" id="syn_NewTechnologiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="VcnPrivateMember" id="syn_VcnPrivateMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CashPaymentsExistingLiabilities" id="syn_CashPaymentsExistingLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ClosingFinanceCosts" id="syn_ClosingFinanceCosts" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BusinessCombinationMilestonePayments" id="syn_BusinessCombinationMilestonePayments" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="OtherFirstIndicationMember" id="syn_OtherFirstIndicationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OtherSecondIndicationMember" id="syn_OtherSecondIndicationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationMilestonePaymentsSafeToProceed" id="syn_BusinessCombinationMilestonePaymentsSafeToProceed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationMilestonePaymentsFirstPatientDosed" id="syn_BusinessCombinationMilestonePaymentsFirstPatientDosed" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationMilestonePaymentsBlaApproval" id="syn_BusinessCombinationMilestonePaymentsBlaApproval" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="GrifolsInnovationMember" id="syn_GrifolsInnovationMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
</xsd:schema>
