荧光寿命测定的现代方法与应用.ppt

***荧光寿命测定的现代方法与应用七彩的荧光荧光及荧光分光光度计的发展荧光寿命的基本原理荧光寿命测定的现代方法及数据处理测定荧光寿命的一些应用测定荧光寿命的仪器主要内容Theemissionoflightfromanysubstanceiscalledluminescence.Someofthefirstscientificreportsofluminescenceappearedinthemiddleofthe18thcentury.In1845,Herschelobservedthatanotherwisecolourlesssolutionofquinine(quinineabsorbsintheUVregion)inwateremittedabluecolourundercertaincircumstances.In1852SirG.G.Stokesstudiedthesamepoundandfoundthattheemittedlighthasalongerwavelengththanthelightabsorbed,theso-calledStokes’shift.(firstdescribedfluorescence)Inthe1920sand1930sJab?ońskiinvestigatedpolarizedlightandfluorescenceandwasabletoshowthatthetransitionmomentsinabsorptionandemissionaretwodifferentthings.TheDevelopmentofFluorescenceThefirstfluorescencemicroscopesweredevelopedbetween1911and1913byGermanphysicistsOttoHeimsttandHeinrichLehmannasaspin-offfromtheultravioletinstrument.Itwasntuntiltheearly1940sthatAlbertCoonsdevelopedatechniqueforlabelingantibodieswithfluorescentdyes,thusgivingbirthtothefieldofimmunofluorescence.Bytheturnofthetwenty-firstcentury,thefieldoffluorescencemicroscopywasresponsibleforarevolutionincellbiology,couplingthepoweroflivecellimagingtohighlyspecificmultiplelabelingofindividualorganellesandmacromolecularplexeswithsyntheticandgeneticallyencodedfluorescentprobes.TheDevelopmentofFluorescenceMicroscopesBasictheoryoffluorescenceLifetimeThephotophysicalprocessesthatoccurfromabsorptiontoemissionareoftenshowninaso-calledJab?ońskidiagram.12荧光是分子吸收能量后其基态电子S0被激发到单线激发态S1或S2后由第一单线激发态S1回到基态S0时所发生的。01荧光寿命是指分子在单线激发态S1所平均停留的时间，或者说处于激发态S1的分子数目衰减到原来的1/e所经历的时间。02由于荧光现象多发生在纳秒级,这正好是分子运动所发生的时间尺度,因此利用荧光技术可以“看”到许多复杂的分子间作用过程,例如超分子体系中分子间的簇集、固液界面上吸附态高分子的构象重排、蛋白质高级结构的变化等。03荧光寿命的概念荧光寿命测定的现代方法1荧光寿命测定的现代方法主要有以下几种，即时