Questions and Answers November 2024 2024年11月关于溶出方法的问题和回复——USP）

Questions andAnswers November2024Margareth R.Marques,Ph.D.and MarkLiddell,Ph.D.The followingquestions havebeen submittedby readersof；Dissolution Technologies.Margareth R.Marques,Ph.D andMarkLiddell,Ph.D.,United StatesPharmacopeia USPauthored7responses toeach of the questions.*Note:These areopinions andinterpretationsoftheauthors andare notnecessarily theofficialviewpoints ofthe USP.Email forcorrespondence:QWe havePeak vesselsin ourlab andwe wouldlike to know iftheperformance verificationprocedure PVTis applicabletothese vessels.APeak is a brandname froma specificmanufacturer.Thegeneric nameof thistype ofvessel isapex vessel.There isno PVTprocedurefor apexvessels.The DissolutionPerformanceVerification Standard-Prednisone tabletswas developedspecificallyfor usewith Apparatus1and Apparatus2as describedin general chapter711Dissolution.The suitabilityof dissolutionequipmentshould beverified usingstandard vessels.Be awarethat,as apexvessels arenot standardized,theirdimensions mayvary fromone supplierto another.Whenreplacing abroken apexvessel,the replacementshould comefrom the samesupplier.Typically apexvessels arethe lastoption,and theiruse requiresjustificationobtained withthe sampleunder evaluation.Beforeusing apexvessels simplyincreasing therotation speedisagoodplace to start tosee ifproblems with a dissolution method canberesolved.QWe aredoing adissolution testwith atablet thathas averylow labelclaim.The dissolution procedure statesto use900mL ofdissolutionmedium andquantification byspectrophotometricprocedure.We areobtaining lowabsorbance values.Can wechangethe volumeto500mLAIf the dissolutionmethodwas developedusing900mL,youcannot changeany ofthe dissolutionconditions withoutajustification.An alternativeway ofsolving thisproblem isto useUV-Vis cellswithalonger pathlength,like5cm or10cm.Thisapproach wouldallow youto obtainhigher absorbancevalueswithout makingany changesto thedissolutionprocedure.QI amdoing someresearch workin tabletdisintegration.As itiswidely known,tablets andcapsules needto disintegratewithin15and30min respectivelyto passthe USPdisintegration test.IAwould liketoknowhow the15-and30-min timingcame about.The15-and30-minute criteriamentioned aboveis simplyasuggestion.Actually,there isno establishedacceptance criteriafordisintegration.The acceptancecriterion fordisintegration isformulation-dependent andmust bejustified withdata obtainedfromthe samplesbeing evaluated.QWhat arethe limitsfor enzymaticactivity ofpepsin to be usedindissolutionAThe limitsfor enzyme activity mentionedingeneralchapter711Dissolution describesthe upperlimit forenzymeactivityinthe dissolutionmedium.Because the activity of enzymes canvaryfrom lotto lot,theactivityof anyenzyme tobe usedindissolution testingmust bedetermined priorto preparingthedissolution medium.Use theprocedure referencedfor eachenzymein theUSP generalchapter711Dissolution.Using theactivityvalue determinedexperimentally,the weightofenzymeiscalculated toobtain theappropriate activityper unitvolume asstatedin

711.QUSP GeneralChapter711states:Time:Where asingle timespecification is given,the testmay beconcluded ina shorterperiodif therequirement for the minimumamount dissolvedismet.Specimens aretobewithdrawn onlyat thestated times,〃within atolerance of±2%.Is thispoint applicablefor manualwithdrawalor forautomated samplingWhat isthe minimumtimesingle timeconsidered forthe tolerancelimit of±2%.,Forexample,if asingle timespecificationisgiven at15minutes,thenit isquite difficultto withdrawalwithin thespecified tolerancelimit.AThe toleranceforthe sampling timeof±2%is applicabletoboth manualand automatedsampling.If the sample isgoing tobetaken at15minutes,the rangetostartthesamplingis15±2%.Keep inmind thatthedissolutionprocess stopsonly whenthedissolving particlesare removedfromthedissolution media.Consequently,sampling includesboth removingthesamplefromthe dissolutionvessel andfiltering thesample.As aresult,earlysampling timepoints canbe challengingfor bothmanual andautomatedsampling methods.。