Description:
ChromogenixCoatest®Heparinisa chromogenicassaykitfortheinvtirodiagnosticphotometricdeterminationofheparininhumanplasma.TheCoatest®Heparintestkitdeterminestheanti-FXaactivityofLMWheparinandUFheparin.ExcellentreagentstABIlity.Suitableforbothlargeandsmalllaboratories.
KitComposition:
Reagents, Packaging,Storage,Stability,andMicroplate/TestTubePreparation
- S-2222™,1vial.Chromogenicsubstrate(Bz-IIe-Glu-(g-OR)-Gly-Arg-pNA·HCl)15mgwithmannitoladdedasabulkingagent.Reconstitutewith20mLsterilewatertoobtainaconcentrationof1mmol/l.Thesolutionisstablefor6monthsat2-8°C.
- FactorXa,1vial.BovineFactorXa71nkat.Reconstitutewith10mLsterilewater.ThereconstitutedFactorXaisstablefor1monthat2-8°Cor6monthsat-20°Corbelow.
- Buffer,stocksolution,1vial.Tris0.5mol/l,pH8.4,10ml.Anopenedvialofstocksolutionisstablefor2monthsat2-8°C.Beforeusediluteaccordingly:1volumeofstocksolutionwith9volumesofsterilewater.
- Antithrombin,1vial.LyophilizedhumanAntithrombin,10IU.Reconstitutewith10mLsterilewatertoobtainaconcentrationof1IU/ml.ThereconstitutedAntithrombinisstablefor1monthat2-8°Cor6monthsat-20°Corbelow.
- NormalPlasma(human),4vials.Lyophiliziedplasma.Reconstitutewith1.00mLsterilewater.Thereconstitutedplasmaisstablefortwoweeksat2-8°Cor1monthat-20°Corbelow.
Whenkeptat2-8°Cthesealedreagentsarestableuntilexpirydateprintedonthelabel.Avoidcontaminationbymicroorganismsinopenedvials.
MeasurementPrinciple:
| AT+ Heparin(excess) | → | [Heparin•AT] |
| [Heparin• AT]+FXa(excess) | → | [Heparin• AT•FXa](excess)+FXa(residual) |
| FXa(residual) | ||
| S-2222™ | → | Peptide+pNA |
Heparinisanalysedasacomplexwithantithrombin(AT)presentinthesample.TheconcentrationofthiscomplexisdependentontheavailabilityofAT.InordertoobtainamoreconstantconcentrationofAT,purifiedATisaddedtothetestplasma.FXa(inexcess)isneutralizedinproportiontotheamountofheparin,whichdeterminestheamountof[Heparin•AT]complex.TheremainingamountofFXahydrolysesthechromogenicsubstrateS-2222™thusliberatingthechromophoricgroup,pNA.Thecoloristhenreadphotometricallyat405nm.
Testperkit:
- Testtube:100
- Microplate:400
- Automated:upto285
Background:
Heparinpreparationsextractedfromanimalshavebeenusedclinicallyforoverhalfacenturyasapotentanticoagulanttherapeuticforthetreatmentandpreventionofthromboticdisease.Bleedingandheparin-inducedthrombocytopeniaarethemainadversereactionsassociatedwithheparintherapy.Theseriskscanbeminimizedbyappropriatepatientmanagementandbylaboratorymonitoringusingspecificchromogenicanti-factorXaassays.Theclinicalindicationsfortheseassaysarereviewedtogetherwithabasicintroductionoftheclinicalpharmacologyofheparin.
Heparinisanaturallyoccurring,highlysulfatedpolysaccharide,characterizedbyawidemolecularweightrangeandpowerfulanticoagulantproperties.SinceitsdiscoverybyMcLeanin1916,heparinhasbecomeawidelyusedanticoagulantforthetreatmentandpreventionofthromboticdiseasesandformaintainingbloodfluidityinextracorporealdevices.Materialforclinicaluseisderivedfromporcineandbovinetissueandispreparedeitherasunfractionated(UF)heparinorasdepolymerizedlowmolecularweight(LMW)heparin.
Themaincomplicationwithheparintherapyisthatitoccasionallycauseslife-threateningbleeding.Laboratorymonitoringwithadjustmentsofdoseregimensisoneoftheoptionsavailablewhichmayimprovetheantithromboticefficacyofheparinandreducetheriskofhemorrhage.However,theidealheparintestanditsclinicalrelevanceisstillacontroversialtopic.
Readmoreaboutheparin.
