简介:通过紫外差谱方法研究金属Fe离子不同形态与不同类别血清白蛋白分子的别构效应,并比较分析分子作用机理.考察氧介导条件对Fe离子不同形态分别与人血清白蛋白(Humanserumalbumin,HSA)、牛血清白蛋白(Bovineserumalbumin,BSA)别构效应的影响,建立定量模型方程.结果表明,Fe离子不同形态与血清白蛋白结合反应体系中存在Fe(Ⅱ)-HSA/BSA~Fe(Ⅲ)-HSA/BSA的动态平衡,Fe(Ⅱ)-HSA/BSA~Fe(Ⅲ)-HSA/BSA电子转移效应是别构效应的关键影响因素,导致Fe离子不同形态与血清白蛋白结合反应的别构效应迥异,呈现形态显著性差异.氧介导及无氧条件下的Fe(Ⅱ)-HSA/BSA~Fe(Ⅲ)-HSA/BSA电子转移效应机理不同.无氧条件下,Fe(Ⅲ)与血清白蛋白的相互作用遵循动力学一级反应规律,计算得到结合反应体系的速率常数k及自由能变ΔG≠.
简介:FiveC3/C3fluoroquinolonedimerstetheredwithafusedheterocyclicringofs-triazolo[2,1-b][1,3,4]thiadiazolederivedfromantibacterialquinolonesweresynthesizedandcharacterized,andtheirinvitroantitumoractivityagainstL1210,CHOcelllineswasevaluatedviatherespectiveIC50values.
简介:密度功能的计算被执行了比较地调查Au(I)的二条可能的小径有炔属羟的-ketoesters的催化Conia-ene反应。我们的研究发现在trifluoromethanesulfonate(TfO)的帮助下面,-ketoester是很可能为II建模经历到isomerize进它的enol形式,TfO通过一个6成员戒指转变状态在起一个质子转移作用。到炔属羟三元组契约的Au(I)催化剂的协作能提高eletrophilic能力和炔属羟一半的反应活动,它在炔属羟一半上触发enol一半的亲核的增加给vinyl-Au中介。这cycloisomerizaion步是由有56.0kJ/mol的一个精力障碍的21.3kJ/mol的exothermal。在整个催化过程,vinyl-Au的protonation是几乎自发的,并且enol的形成是限制率的步。enol的产生和炔属羟上的Au(I)催化剂的激活是Conia-ene反应能处于温和状况发生的关键原因。Au(I)催化的这些计算支持有炔属羟的-ketoesters的Conia-ene反应通过2由Toste建议了的小径。
简介:CardiactroponinI(cTnI)wasseparatedandpurifiedfromhumanleftventriculartissuebyaffinitychromatographicmethodandusedtoimmunizeBalb/cmicebyintraperitonealinjectionandfourhybridomacelllines,whichsecretedmonoclonalantibody(mAb)againsthumancTnI,wereobtainedbycellfusion,identificationandcloningtwice.ThreemAbs(9F5,2F11,8C12)wereproducedfromtheascitesofBalb/cmiceinjectedintraperitoneallythehybridomacellsandcharacterizedbymeansofasurfaceplasmonresonance(SPR)biosensor.AnoptimalandspecificsensingmembranefortroponinIwaspreparedwithstaphylococcalproteinA(SPA)astheintermediatelayerandmAbagainsthumancTnIasthecaptureantibody.Onthebasisofthesensingmembrane,twomodesofoperationoftheSPRbiosensorweredeveloped,i.e.,adirectdetectionofantigen-antibodyaffinityandasandwichassay.Inthesandwichassaydetectionmode,themAbscompetitionwasmeasuredbymonitoringwhetherthesecondaryantibodyhadbeenattachedtothecTnIalreadycapturedbythefirstantibodyonthesensorsurface.TheSPRbiosensorwasshowntobeabletodirectlydetecttheantigen-antibodyaffinityandtheorderoftheaffinitywasfoundtobe9F5>2F11>8C12.Inthesandwichdetectionmode,itwasfoundthatthedifferentepitopesonthecTnImoleculeswererecognizedbythethreemAbsrespectively,buttheasymmetricalcompetitionwasshownbetween2F11and8C12andnocompetitionwasfoundbetween9F5and2F11or8c12.Basedontheseresults,adoublemonoclonalsandwichimmunoassayforcTnIwasdevelopedbyusingtheoptimalantibodypairof9F5and2F11andtheSPRbiosensorwithSPAsubstratemembrane,whichshowedanexcellentsensitivityof0.8μg/LforboththebufferandtheserumsamplescomparedwiththedirectdetectionofcTnIforthebufferwiththelowestdetectionlimitof4μg/LandconventionalELISAwiththesensitivityof1.9μg/L.
简介:Thestrueturaleffectoftheconjugativesystem(C)withcarbonyl-iminobridgeshasbeenstudied.Theresultsshowthat:Intheconjugatedsystem(C),thereisnoelectronicabsorptionpeakattributabletothewholesystem,buttherearethreeπ-π*bandseachntwhichdisplayschacactecisticsofitsownindependently.Theseindicatethatthetwobridges-carbonyl-and-imino-canblockthetlanSmlSSionoftheconjngativepolarizationofthewholesystem,soastoformthreesegments,thisisverifiedbymeansofchemicalsynthesisanddegradation.
简介:NaphtholgreenBwasused,forthefirsttime,asanewmediatorinanamperometricglucosebiosensor.Itisagoodmediator,promotingelectrontransferfromglucoseoxidasetographiteelectrode.Thebiosensorshowshighsensitivitytoglucoseatlowpotentialwithresponsetimeof30seconds.Thelinearrangeisfrom1.5to18μmol/Lglucosewithdetectionlimitof0.5μmol/Lglucose.
简介:Understeady-stateconditions,thegeneralcurrentsofEEreactionsatdisk,hemisphericalandsphericalmicroelectrodesarederived.Fromtheseequations,someelectrodereactionparameterscanbeverysimplyobtained.
简介:Copolymerizationofstyrene(St)andisoprene(IP)wascarriedoutwithacatalystsystemcomposeaofanhydrouslanthanidechloridehexamethylphosphoramidecomplex(LnCl3·HMPA)andaluminumorganiccompound(AOC).Amongthecatalystsexamined,catalystNdCl3·HMPA/AI(i-Bu)3showedahighactivityinthecopolymerizationundercertainconditionsgivingcopolymers(5%—15%Stcontent)withhighcis-1,4microstructureinIPunits(>95%).TheeffectsofHMPA/Ndmolarratio,Al/Ndmolarratio,monomer/Ndmolarratio,Stfeedratio,andthereactiontimeoncopolymerizationwereexaminedwiththiscatalyticsystem.Theobtainedcopolymerswerecharacterizedby^1Hand^13CNMRspectroscopiesandgel-permeationchromatography(GPC).
简介:AbinitiomolecularorbitalcalculationsofdoublynegativechargedB16H162-(D2)andneutralB16H16(Td)havebeendoneattheHF/6-31Glevel.TheyarepredictedtobechemicallyandkineticallystablebyvibrationalanalysesontheirrespectiveenergyhypersurfaceoftheHF/6-31Glevel.ThegeometricalstructureofthespeciesB16H1622-(D2)wasdiscussed.
简介:FluorescencequenchingofjanusgreenB(JGB)insodiumdodecylsulfate(SDS)micellebynucleicacids(DNA)wasstudiedusingUV-visabsorption,steadystatefluorescenceemissionmethodsandlifetimemeasurements.IntheSDSmicelle,weakfluorescenceofJGBwasenhanced,andthemaximumemissionshiftedfrom425to410nm.InthepresenceofDNA,thefluorescenceofJGBwasquenched.Linearrelationshipsbetweenthefluorescencequenching(F0/F)andconcentrationsofDNAwereobservedintherangeof2.4×10^-8to1.08×10^-7mol·L^-1forcalfthymusnucleicacids(ctDNA)and1.9×10^-8to3.8×10^-8mol·L-1forfishspermnucleicacids(fsDNA)when2.5×10^-5mol·L^-1JGBwasemployed.Thelimitdetectionwere1.3×10^-8mol·L^-1forctDNAand6.4×10^-9mol·L^-1forfsDNA.AthighDNAconcentration,therewasasystematicdeviationfromtheStem-Volmerequationduetothestaticanddynamicquenchingoccurringsimultaneously.TheproposedmethodwasappliedtothedeterminationofthenucleicacidsinchickenbloodextractionandtheanalyticalresultswereingoodagreementwiththeUV-method.