離子液體在色譜中的應用

離子液體在色譜中的應用第1頁，課件共16頁，創(chuàng)作于2023年2月高效液相色譜法包括正相高效液相色譜法和反相高效液相色譜法。正相高效液相色譜法中流動相的極性小于固定相的極性，也就是以及性鍵合相為固定相（常以氨基、氰基鍵合相等作為固定相）。反相高效液相色譜法中流動相的極性大于固定相的極性，也就是以非極性鍵合相為固定相（常以十八硅烷C18、辛烷C8、甲基C1、苯基等作為固定相）。

離子對試劑是由強親水離子形成，反作用于樣品分子中的中性離心子對。因此，可用于同時分離帶電分子和非帶電分子。一般適用所有色譜固定相，流動相含水至少達10％，否則就有產(chǎn)生沉淀的危險（特別是在使用乙腈的情況下）。當使用長鏈的離子對試劑時，如十六烷基硫酸銨或十二烷基硫酸鈉，色譜柱將選用反相色譜柱。2第2頁，課件共16頁，創(chuàng)作于2023年2月

抗衡離子：在離子型聚合反應中，存在于增長鏈末端活性離子附近的相反電性離子。

洗脫與洗脫劑：在洗脫色譜操作中，流動相攜帶待測組分在色譜柱內(nèi)向錢移動并流出色譜柱的過程稱為洗脫。所用流動相稱為洗脫劑。3第3頁，課件共16頁，創(chuàng)作于2023年2月2.反相高效液相色譜法中離子液體作為流動相添加劑對兒茶酚胺保留值的影響3.離子交換色譜法和反相高效液相色譜法分析選定的離子液體陽離子4.1-烷基3-甲基咪唑離子液體作為洗脫劑對液相色譜法分離麻黃素的影響1.反相液相色譜法測定選擇性室溫離子液體陽離子5.離子液體雙水相體系，高效液相色譜法測定鴉片生物堿的樣品前處理過程4第4頁，課件共16頁，創(chuàng)作于2023年2月6.使用四氟硼酸咪唑離子液體抑制液相色譜分析中游離硅羥基的不利影響7.離子液體在液體色譜法中減少硅羥基的相互作用

8.基于離子液體的液相微萃取-高效液相色譜法測定水中有機磷農(nóng)藥9.液體作為高效液相色譜分析的添加劑：分析胺和離子液體的相互作用機制10.離子液體液液萃取-高效液相色譜測定水中酚類化合物5第5頁，課件共16頁，創(chuàng)作于2023年2月1.Reversed-phaseliquidchromatographicmethodforthedeterminationofselectedroom-temperatureionicliquidcations

Abstract

Theseparationofselected1-alkyl-and1-aryl-3-methylimidazolium-basedroomtemperatureionicliquidcationshasbeenperformedusingreversed-phasehigh-performanceliquidchromatographywithelectrosprayionizationmassdetection.TheRP-HPLCmethoddevelopmentstartedwiththeselectionofacolumntakingintoaccountespeciallytheresolutionoflowmolecularcongenersoftheselectedgroup.Mobilephasecompositionwasoptimizedforpeakresolution,sensitivityandhighreproducibilityofretentionvalues.Theresultsofthemethoddevelopmentwereappliedtothedeterminationofexemplaryionicliquidspeciespresentinthemediumusedincytotoxicitystudies.6第6頁，課件共16頁，創(chuàng)作于2023年2月2.EffectofIonicLiquidsasMobilePhaseAdditivesonRetentionofCatecholaminesinReversed-PhaseHigh-PerformanceLiquidChromatography

Abstract

Ionicliquidsorroomtemperatureionicliquidshavebeenwidelyinvestigatedasnewsolventsforcatalysisinthepastseveralyears.Becauseofsomespecialpropertiesofionicliquids,interestofusingthemindifferentchemicalprocessesisincreasing.Thisworkreportsontheuseof1-alkyl-3-methylimidazoliumsaltsandN-butyl-pyridiniumsaltsasnewmobilephaseadditivesforseparationofcatecholaminesinreversed-phasehigh-performanceliquidchromatography.Thegoodseparationisachievedbyusingtheseadditives.DifferentpHvaluesofthemobilephase,concentrationofionicliquids,anddifferentalkylsubstituentsonthecationsordifferentcounterionofionicliquidswereinvestigated.Theseparationmechanisminvolvesmolecularinteractionsbetweenionicliquidsandcatecholamines.

7第7頁，課件共16頁，創(chuàng)作于2023年2月3.Analysisofselectedionicliquidcationsbyionexchangechromatographyandreversed-phasehighperformanceliquidchromatography

Abstract

Thechromatographicbehaviorofionicliquids-homologuesof1-alkyl-3-methylimidazoliumand4-methyl-N-butylpyridinium-hasbeeninvestigatedwithastrongcationexchangeadsorbent.Inparticular,thedependenceoftheretentionpropertiesofthesesolutesonmobilephasecomposition,pH,andbufferconcentrationwasevaluatedwiththeaimofoptimizingandimprovingtheselectivityandretentionofsoluteseparation.WhileusingtheSCXstationaryphase,severalinteractionsoccurredwithvaryingstrengths,dependingonthemobilephasecomposition.Cationexchange,nonspecifichydrophobicinteractions,andadsorptionchromatographybehaviorwereobserved.Reversedphasechromatographyoccurredatlowconcentrationsofacetonitrile,electrostaticandadsorptioninteractionsathigherorganicmodifierconcentrations.Elevatedbufferconcentrationsloweredtheretentionfactorswithoutaffectingtheselectivityofionicliquids.Obtainedresultswerefurthercomparedtothechromatographicbehaviourofionicliquidsinthereversedphasesystem.Allanalyzedionicliquidsfollowreversed-phasebehaviorwhilebeingseparated.Muchlowerselectivityintherangeofhighlyhydrophiliccompoundsisobtained.Thissuggestspreferreduseofionchromatographyforseparationandanalysisofcompoundsbelow4carbonatomsinthealkylsidechain.

8第8頁，課件共16頁，創(chuàng)作于2023年2月4.Effectof1-alkyl-3-methylimidazolium-basedionicliquidsastheeluentontheseparationofephedrinesbyliquidchromatography

Abstract

Thechromatographicbehaviorofephedrines(norephedrine,ephedrine,pseudoephedrineandmethylephedrine)onaC18columnwasstudiedwithdifferentconcentrationsof1-butyl-3-methylimidazoliumtetrafluoroborateionicliquidsastheeluentatpH3.0.Theadditionofionicliquidhasgreateffectsontheseparationofthesebasiccompounds:decreasingbandtailing,reducingbandbroadening,andimprovingresolution.Theretentiontimesoftheanalytesincreaseatfirstandthendecreasewiththeincreaseintheconcentrationofionicliquid.Thiseffectmaybeattributedtothecompetitionbetweenimidazoliumcationsandthepolargroupsoftheanalytesforthesilanolgrouponthealkylsilicasurface,andalsototheformationofweakbilayerelectronicstructureontheC18column.Severalionicliquidswithdifferentalkylsubstituentsontheimidazoliumcationsorwithdifferentcounterionsastheeluentswerecompared.9第9頁，課件共16頁，創(chuàng)作于2023年2月5.Ionicliquid-basedaqueoustwo-phasesystem,asamplepretreatmentprocedurepriortohigh-performanceliquidchromatographyofopiumalkaloids

Abstract

Anionicliquid,1-butyl-3-methylimidazoliumchloride([C4mim]Cl)/saltaqueoustwo-phasesystems(ATPS)waspresentedasasimple,rapidandeffectivesamplepretreatmenttechniquecoupledwithhigh-performanceliquidchromatography(HPLC)foranalysisofthemajoropiumalkaloidsinPericarpiumpapaveris.Tofindoptimalconditions,thepartitionbehaviorsofcodeineandpapaverineinionicliquid/saltaqueoustwo-phasesystemswereinvestigated.Variousfactorswereconsideredsystematically,andtheresultsindicatedthatboththepHvalueandthesalting-outabilityofsalthadgreatinfluenceonphaseseparation.Therecoveriesofcodeineandpapaverinewere90.0–100.2%and99.3–102.0%,respectively,fromaqueoussamplesofP.papaverisbytheproposedmethod.10第10頁，課件共16頁，創(chuàng)作于2023年2月6.Suppressionofdeleteriouseffectsoffreesilanolsinliquidchromatographybyimidazoliumtetrafluoroborateionicliquids

Abstract

Silica-basedstationaryphasesarecommonlyusedinliquidchromatography,buttheirsurfaceaciditycausesknownproblems,especiallywhenseparatingbasiccompounds.Deleteriouseffectsoffreesilanolsarenotfullyremovedbystandardpreventionproceduresconsistinginaddingalkylaminesorotheraminoquencherstotheeluents.Wefoundthationicliquidsoftheimidazoliumtetrafluoroborateclass,addedtomobilephasesatconcentrationsof0.5–1.5%(v/v),blockedsilanolsandprovidedexcellentthin-layerchromatographicseparationsofstronglybasicdrugswhichwereotherwisenoteluted,evenwithneatacetonitrileasthemobilephase.Thesilanolsuppressingpotencyofimidazoliumtetrafluoroborateswasdemonstratedtomarkedlyexceedthatofthestandardmobilephaseadditives,liketriethylamine,dimethyloctylamineandammonia.Theproposednewmobilephaseadditiveswerealsodemonstratedtoprovidereliablelipophilicityparametersofbasedruganalytesasdeterminedbygradientmodeofhigh-performanceliquidchromatography.Byapplyingthereadilyavailableandenvironmentallyfriendlyimidazoliumtetrafluoroborateionicliquids,simpleandefficientmeansofimprovementofliquidchromatographicanalysisoforganicbaseswereelaborated.11第11頁，課件共16頁，創(chuàng)作于2023年2月7.Reductionofsilanophilicinteractionsinliquidchromatographywiththeuseofionicliquids

Abstract

Asuppressionofsilanophilicinteractionsbytheselectedionicliquidsaddedtothemobilephaseinthin-layerchromatography(TLC)andhigh-performanceliquidchromatography(HPLC)isreported.Acetonitrilewasusedastheeluent,aloneorwithvariousconcentrationsofwaterandphosphoricbufferpH3.Selectivityofthenormal(NP)andthereversed(RP)stationaryphasematerialwasexaminedusingaseriesofproton-acceptorbasicdrugsanalytes.TheionicliquidsstudiedappearedtosignificantlyaffectanalyteretentioninNP-TLC,RP-TLCandRP-HPLCsystemstested.Consequently,theincreasedseparationselectivitywasattained.Duetoionicliquidadditivestoeluentevenanalytescouldbechromatographed,whichwerenotelutedfromthesilica-basedstationaryphasematerialswith100%ofacetonitrileinthemobilephase.Additionofionicliquidalreadyinverysmallconcentration(0.5%,v/v)couldreducetheamountofacetonitrileusedduringtheoptimizationofbasicanalytesseparationsinTLCandHPLCsystems.Moreover,theinfluenceoftemperatureontheseparationofbasicanalyteswasdemonstratedandconsideredinpracticalHPLCmethoddevelopment.12第12頁，課件共16頁，創(chuàng)作于2023年2月8.DeterminationofOrganophosphorousPesticidesinWaterSamplesUsingIonicLiquid-basedLiquidPhaseMicroextractionCoupledwithHighPerformanceLiquidChromatographyXie

Abstract

Anovelmethodforthedeterminationofthreeorganophosphorouspesticides(phorate,parathionandpoxim)inwatersampleshasbeendevelopedusingionicliquid-basedliquid-phasemicroextractioncoupledwithhighperformanceliquidchromatography.Theinfluenceofextractionparametersincludingextractionsolvent,thevolumeratioofextractionsolventtosampleaqueous,extractiontime,extractiontemperatureandstirringratewasinvestigated.1-butyl-3-methylimidazoliumhexafluorophosphatewasusedasextractionsolventanddisplayedparticularadvantagescomparedwithvolatileorganicsolventssuchasbenzene,hexaneandacetone.Theproposedmethodprovidedenrichmentfoldsof665,630and553forphorate,parathionandpoxim,respectively.Themethodhadgoodlinearrangeof0.01-0.1μL/Landthelimitsofdetectionofthethreepesticideswereintherangeof0.001-0.01μL/L.TheRSDofmatrixspikedsampleswere3.4%,10.5%and2.4%forphorate,parathionandpoxim,respectively.13第13頁，課件共16頁，創(chuàng)作于2023年2月9.Ionicliquidsasadditivesinhighperformanceliquidchromatography:Analysisofaminesandtheinteractionmechanismofionicliquids

Abstract

Asnovelsolvents,ionicliquidshavemanyapplicationsinsynthesis,catalysisandanalyticalseparation,i.e.extractionandchromatographyseparation.Inthispaper,someaminesincludingbenzidine,benzylamine,N-ethylanilineandN,N′-dimethylanilineareseparatedusingionicliquidsasadditivesforthemobilephaseinhighperformanceliquidchromatography(HPLC).Theeffectsofthelengthofalkylchainorcounterionsondifferentionicliquidsandtheirconcentrationsontheseparationoftheseanalytesareperformed.Thedifferencesbetweenionicliquidsandtetrabutylammoniumbromide(TBA)ontheseparationofo-,m-,p-phthalicacidsarecomparedandtheresultsshowthationicliquidsareion-pairreagentsinessence,althoughtheirhydrophobicityandhydrogenbondingalsoplayimportantroles.14第14頁，課件共16頁，創(chuàng)作于2023年2月10.AnalysisofPhenolicCompoundsbyIonicLiquidBasedLiquidLiquidExtractionCoupledwithHighPerformanceLiquidChromatogra