X-raypowderdiffraction(XRPD)isawidelyusedanalyticaltechniqueforthecharacterizationofcrystallineandpartiallycrystallinesolidsinthepharmaceuticalindustry.TheUnitedStatesPharmacopeia(USP)providesguidelinesandstandardsforXRPDanalysisinUSP41-NF36toensurethequalityandconsistencyofdrugsubstancesandproducts.XRPDisanon-destructivemethodthatprovidesinformationaboutthecrystalstructure,phasecomposition,anddegreeofcrystallinityofsolidmaterials.Itisparticularlyusefulforidentifyingpolymorphs,hydrates,solvates,andamorphouscontentinpharmaceuticalcompounds.ThetechniquereliesonthediffractionpatternproducedwhenX-raysinteractwiththeorderedatomicplanesinacrystallinematerial.USP41-NF36outlinesthegeneralprinciples,instrumentation,samplepreparation,anddatainterpretationforXRPDanalysis.Compliancewiththesestandardsensuresreliableandreproducibleresults,whicharecriticalfordrugdevelopment,qualitycontrol,andregulatorysubmissions.Themethodisapplicabletobothactivepharmaceuticalingredients(APIs)andexcipients,helpingtoconfirmidentity,purity,andstability.ByfollowingtheUSPguidelines,laboratoriescanperformXRPDanalysiswithconfidence,supportingthecharacterizationofsolid-statepropertiesessentialforpharmaceuticalformulationandmanufacturing.
