90plus纳米粒度仪应用案例
文献名：reducingliposomesizewithultrasound:bimodalsizedistributions
作者：dixonj.woodbury,erics.richardson,aaronw.grigg,rodneyd.wellingandbrianh.knudson
departmentofphysiologyanddevelopmentalbiology,brighamyounguniversity,provo,ut,usa
departmentofphysiologyanddevelopmentalbiology,provo,ut,usa
摘要：sonicationisasimplemethodforreducingthesizeofliposomes.wereportthesizedistributionsofliposomesasafunctionofsonicationtimeusingthreedifferenttechniques.liposomes,mildlysonicatedforjust30sec,hadbimodaldistributionswhensurface-weightedwithmodesatabout140and750nm.withextendedsonication,thesizedistributionremainsbimodalbuttheaveragediameterofeachpopulationdecreasesandthesmallerpopulationbecomesmorenumerous.independentmeasurementsofliposomesizeusingdynamiclightscattering(dls),transmissionelectronmicroscopy(tem),andthenystatin/ergosterolfusionassayallgaveconsistentresults.thebimodaldistribution(evenwhennumber-weighted)differsfromtheweibulldistributioncommonlyobservedforliposomessonicatedathighpowersoverlongperiodsoftimeandsuggeststhatadifferentmechanismmaybeinvolvedinmildsonication.theobservationsareconsistentwiththefollowingmechanismfordecreasingliposomesize.duringultrasonicirradiation,cavitation,causedbyoscillatingmicrobubbles,producesshearfields.largeliposomesthatenterthesefieldsformlongtube-likeappendagesthatcanpinch-offintosmallerliposomes.thisproposedmechanismisconsistentwithcolloidaltheoryandtheobservedbehaviorofliposomesinshearfields.
关键词：sonication,liposome,dynamiclightscattering(dls),transmissionelectronmicroscopy(tem),acousticmicrostreaming,colloidsinshearfields