Designation:F2149−16StandardTestMethodforAutomatedAnalysesofCells—theElectricalSensingZoneMethodofEnumeratingandSizingSingleCellSuspensions1ThisstandardisissuedunderthefixeddesignationF2149;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginaladoptionor,inthecaseofrevision,theyearoflastrevision.Anumberinparenthesesindicatestheyearoflastreapproval.Asuperscriptepsilon(´)indicatesaneditorialchangesincethelastrevisionorreapproval.1.Scope1.1Thistestmethod,providedthelimitationsareunderstood,coversaprocedureforboththeenumerationandmeasurementofsizedistributionofmostallcelltypes.Theinstrumentationallowsforuser-selectablecellsizesettingsandisapplicabletoawiderangeofcelltypes.Themethodworksbestforsphericalcells,andmaybelessaccurateifcellsarenotspherical,suchasfordiscoidcellsorbuddingyeast.Themethodisappropriateforsuspensionaswellasadherentcellcultures(1).2Resultsmaybereportedasnumberofcellspermilliliterortotalnumberofcellspervolumeofcellsuspensionanalyzed.Sizedistributionmaybeexpressedincelldiameterorvolume.1.2Cellscommonlyusedintissue-engineeredmedicalproducts(2)areanalyzedroutinely.Examplesarechondro-cytes(3),fibroblasts(4),andkeratinocytes(5).Szaboetal.usedthemethodforbothpancreaticisletnumberandvolumemeasurements(6).Inaddition,instrumentationusingtheelec-tricalsensingzonetechnologywasusedforbothcountandsizedistributionanalysesofporcinehepatocytesplacedintohollowfibercartridgeextracorporealliverassistsystems.Inthisstudy(7),andothers(6,8),theautomatedelectricalsensingzonemethodwasvalidatedforprecisionwhencomparedtotheconventionalvisualcellcountingunderamicroscopeusingahemocytometer.Currently,itisnotpossibletovalidatecellcountingdevicesforaccuracy,sincetherenotawaytoproduceareferencesamplethathasaknownnumberofcells.Theelectricalsensingzonemethodshallbevalidatedeachtimeitisimplementedinanewlaboratory,itisusedonanewcelltype,orthecellcountingprocedureismodified.1.3Electricalsensingzoneinstrumentation(commonlyre-ferredtoasaCoultercounter)ismanufacturedbyav...
