超临界流体萃取及层析

WhatisaSupercriticalFluid?Whenthepressureandtemperatureofasubstanceisraisedaboveitscriticalpressureandcriticaltemperature(thecriticalpoint)thesubstanceentersthesupercriticalstate.ASupercriticalFluidisasubstancewithbothgas-andliquid-likeproperties.CriticalTemperatureandPressureTheCriticalTemperature(Tc)isthemaximumtemperatureatwhichagascanbeconvertedtoaliquidbyincreasingthepressure.TheCriticalPressure(Pc)isthemaximumpressureatwhichaliquidcanbeconvertedtoagasbyincreasingthetemperature.PhaseDiagramofCarbonDioxideTemperatureSupercritical

FluidSolidLiquidTriplePointCriticalPoint31.3

oC,1072psiPressureGasPhysicalPropertiesofCO2PhaseGasSCFLiquidDensity0.6–2.0x10-30.2–0.90.8–1.0viscosity0.5–3.5x10-42.0–9.9x10-40.3–2.4x10-2Diffusivity0.01–1.00.5–3.3x10-40.5–2.0x10-5AdvantagesofSupercriticalFluidsassolventsSolvatingpowerrelatedtodensity

(atconstantT)Gas-likemasstransportpropertiesFacilepenetrationintoporousmaterialCriticalParametersofCommonFluidsTc(°C)Pc(atm)

c(gmL-1)CO231.372.90.47N2O36.572.50.45SF245.537.10.74NH3132.5112.50.24H2O3742270.34n-C4H1015237.50.23n-C6H1219733.30.23Xe16.658.41.10CCl2F211240.70.56CHF325.946.90.52Source:“SFEandItsuseinChromatographicSamplePreparation”Ed.S.Westwood.Chapter1AdvantagesofCO2forSFELowcriticalparametersInert,Non-toxic,Nonflammable,Non-corrosiveEasilypurified(inexpensive)Nonpolar:dielectricconstantsimilartohexaneModifierscanbeusedtoincreasepolaritySupercriticalFluidExtraction(SFE)BasicTheoryRestrictorCO2samplecellinheatedchamberCO2TrapSolidorLiquidModifierPumpSFESystemComponentsCO2Pump(highpressure)LiquidCarbonDioxide(requiresadiptube)AdvantagesofSFEoverSolventExtractionFasterResultsinminutesratherthanhoursSelectivityresultsincleanerextractsLowCriticalParametersHandlingofthermallylabileanalytesNon-hazardoussolventsAutomatedCostpertestislowerLimitedornosolventremovalrequiredNosolventdisposalcostsTheMechanismofSFEAThreeStepProcessDissolving/Resolvinganalyte(s)2.Sweepingtheanalyte(s)fromthematrix3.Trappingtheanalyte(s)SFEMechanismSC-CO2+dissolvedanalytetothetrapHighPressureLiquidCO2SC-CO2diffusesmatrix,dissolvesandresolvesanalytefromthematrixHeatTrappingTrappingSolidHighSurfaceAreaAdequateAmountTrappingLiquidHighSurfaceTensionAnalyteisSolubleLowVolatilityPressurizedCryogenicallyCooledGaseousCO2GaseousCO2CO2ischangingfromaSF(2ml/min)toanexpandedgas(1L/min)AnalytenolongersolubleMechanicalmovementofanalyteduetotherapidexpansionrequirestheuseoftrappingmaterialSFE-MethodDevelopmentPressureIncreasepressureincreasesdensity=increaseinsolubilizingpower.TemperatureIncreasetemperaturemaydecreasesdensity=decreaseinsolubilizingpower(ieCO2at100bar)ExtractionTimeFlowRateFluidCompositionCo-solvents/modifiersReactantAdditiveStaticvs.DynamicExtractionWhyUseModifiers?

Analytesthathavepolarcomponentsrequiretheuseofaco-solventTriglycerides

CH2OCOR1R2COOCHCH2OCOR3

CH2OCOR1R2COOCHOCH2OPOR3

O-PhospholipidsR1&2groupsarelongchainhydrocarbons(nonpolar),whileR3containsphosphorusandnitrogenandispolarR1,2&3groupsarelongchainhydrocarbons(nonpolar)Modifiers(Co-solvents)inSFERoleofModifiersinSFEChangesinSolventPolarityInteractionwithMatrixInteractionwithAnalyteMethodsofAdditionDirectlyintoextractioncell(spiking)Onlinemodifieraddition(usesasecondpump)SFEvs.TraditionalSampleExtractionMethodsConclusionSFEcanbeversatile,selectiveandfasterSFEreduceshazardoussolventuseandcostSFEcanproducecleaner,moreconcentratedextractsforpostextractionanalysisAnalyst’sTimeAllotmentRoutineandNovelApplicationsofAnalyticalSFESFEforResearchEnvironmentalSFEApplicationsMatricesSoilTissueClaySandyLoamSludgeRiverSedimentMarineSedimentFlyAshIncineratorAshTargetAnalytesTPHPAHPCBsPesticidesDibenzofuransDioxinsApprovedMethodsEnvironmentalUSEPA3560-TPHinSoil:SupercriticalFluidExtractionofTotalRecoverablePetroleumHydrocarbons

USEPA3561-PAHinSoil:SupercriticalFluidExtractionofPolyaromaticHydrocarbons

USEPA3562-PCBandOCP:SupercriticalFluidExtractionofPolychlorinatedBiphenyls(PCBs)andOrganochlorine

USEPA3545:PressurizedFluidExtraction(PFE)USDOESTD-3013-99:DeterminationofResidualWaterinImpurePlutoniumOxidesAOACdraft:SFE-GC/MSdeterminationofpesticideresiduesinnon-fattyfruitsandvegetables

Pharmaceutical/NaturalProductApplications

SFEofNaturalProducts--RogerM.Smith

LC-GCInternational,Jan.1996,9-15Catharanthus

roseusGermanchamomileMagnoliagrandifloraTansyChamomileflowerheadsGingerPeppermintThymeCloveOilKolanutsPimentoTurmericDragonheadLavenderPoppyseedsWheatgermoilEnglishyewLemongrassRosemaryFeverfewLemonpeelSavoryMicrobialNaturalProducts

R.M.Smith,op.cit.OrganismExtractAgaricusspeciesCarboxylicandfattyacidsBeuveria

niveaCyclosporinFilamentousfungiPolyunsaturatedfattyacidsFlour,moldybread,mushroomsErgosterolMoldybranSterolMoldygrainAflatoxinExtractsfromBiomass

R.M.Smith,op.cit.MicroorganismExtractActinomycetespeciesMycoluteinandluteoreticulinActinomycetespeciesOligomycinAAspergillus

fumigatusSydowininBandepoxideBipolaris

urochloaeOphiobolinAPenicillium

expansumChaetoglobosinAPenicillium

sclerotium(+)-SclerotiorinStreptomycesspeciesElaiophylinSummary

R.M.Smith,op.cit.Extractstypicallycleanerthanthoseobtainedwithorganicsolvents.Mildconditionsminimizedegradation.SFEmethodsarefasterthanorganicsolventextractions.ExtractionofPharmaceuticalsUsingPressurizedCarbonDioxide

J.R.Dean,S.Khundker,J.Pharm.&Biomed.Anal,15(1997)875-886Recoveriesfrom81%-95+%CO2andCO2withmodifiersGenerallyfasterthanothermethodswithbetterselectivityfortargetanalytes.Preconcentrationstepscouldbeeliminatedinsomecases.LiquidmatricesrequiredimmobilizationonsolidsupportorSPEcartridge.AnimalFeeds

J.R.Dean,S.Khundker,op.cit.AnalyteMatrixMenadioneRatchowTipradaneRodentdietHypolipidermicdrugRatfeedHalogenatedaromaticphenoxyderivativesDogfeed/rodentfeedAtovaquoneRatfeedFluconazoleAnimalfeedPropanolol,Tamoxifen,ZM95527,169369RodentdietFormulations

J.R.Dean,S.Khundker,op.cit.AnalyteMatrixMegesterolAcetateTabletFelodipineTabletBenzodiazipines(7)Tablet/capsuleCaffeine,vanillinTabletVitaminA,ETabletRetinolpalmitate,tocopherolacetateOintmentPolymyxinBsulphateCream/OintmentAcylvoirOintmentSulfamethazole,trimethoprimSeptrainfusionTriamincinoloneDermatologicalpatchesMisoprostolHydroxypropylmethylcelluloseBiologicalMatrices

J.R.Dean,S.Khundker,op.cit.AnalyteMatrixVeterinarydrugs(4)PigkidneyNitrobenzamideresidueLiverCodeine,morphine,ethylmorphineHairKetorolac,flavonePlasmaMebervinealcoholDogplasmaMorphineSerumBeudesonidePlasmaCaffeineKolanutsTaxanesYewtreeneedlesChineseherbalmedicinesPlantsDiosgeninTubersofDioscorea

nipponicaTaxolandbaccatinIIINeedlesofTaxus

cuspidataZingiber

zerumetrhizomesPlantsMevinolinandhydroxyacidformFermentationbrothPhylloquinoneSoyproteinandinfantformulaMiscellaneous

J.R.Dean,S.Khundker,op.cit.AnalyteMatrixTriprolidine,pseudoephedrineAqueousSteroids(10)AqueousIbuprofenAqueousNaturalMaterialsStudied

M.J.Noh,et.al.,op.cit.SpecificNamePartUsedLycium

chineseFruitSchizandre

chinensisFruitCitrusunshiuFruitbarkAngelicagigasRootCornus

officinalisFruitCnidium

officinaleRhizomeGinko

bilobaLeafAralia

cordataRootEvodia

officinalisFruitCrataegus

pinnatifidaFruitPaeonia

lactifloraRootLeonurus

sibricusAllSophorajaponicaFlowerArtemisiacapillarisAllPlatago

asiaticaSeedNaturalMaterialsStudied,contd.

M.J.Noh,et.al.,op.cit.SpecificNamePartUsedEphedra

sinicaAllAconitumcarmichaeliTuberScolopendra

subspinesAllPaeonia

suffruticosaRootPueraria

thunbergianaRootPolygalatenuifoliaRootCoptisjaponicaRhizomeAstragalus

membranaceusRootEucommia

ulmoidesStembarkBupeuri

falcatumRootAcanthopanax

sessiliflorumBarkEpimedium

koreaumAllMorusalbaRootbarkArtium

lappaFruitSpirodela

polyrhizaAllSummary

M.J.Noh,et.al.,op.citFormanymaterials,SFEyieldedextractswithhigherbioactivitythanLSE.SFEwasfoundtobemoreselectivethanLSEfortargetcompounds.SFEconditionscouldbeoptimizedtoproducemaximumlevelsofbioactivity.DrugResiduesAnalyteMatrixReferenceSulfamethazineSwineMuscleTissueCross,et.al.AnabolicSteriodsBovineTissue(MuscleandLiver)HoupalahtiandHenionOpiatesHair,bloodandtissueMultipleAuthorsTemazepamWholeBloodScottandOliverCocaine,benzoylecgonine,codeineandmorphineHairBrewer,et.al.StudySummaryComparedtoaconventionalSPEmethod,theSFEmethodwasmoreefficientandgavecleanerextractswithrecoveriesabove80%K.S.Scott,J.S.Oliver,J.Anal.Toxicol.21(1997)297.SupercriticalFluidChromatography

SFCisaseparationtechniquesimilartoHPLCandGCwherethemobilephaseorcarriergasisreplacedbyasupercriticalfluidLimitationsofGCandHPLCGCSampleLimitations:

VolatilityThermalstabilityLowmolecularweightHPLCAnalyticalLimitations:NouniversaldetectorLowefficiencyLowresolution

SFC

OvercomesLimitationsofGCandHPLCExtendsmolecularweightrangeofGCLoweroperatingtemperaturethanGCFasterseparationtimethanHPLCHigherseparationefficiencythanHPLCUniversaldetectorcanbeused,FIDBothpacked(HPLC-type)andGC-typecolumnscanbeusedCarbonDioxide,CO2

hasdesirablepropertiesasaSFCsolventInexpensiveHighlypureVerylowUVabsorbanceNOFIDbackgroundnoiseLowcriticalpress