QCM Coated with Self-assembled Cystine-bearing 1,3-Bridged Calix[4]arenes for Recognizing Gas-phase Butylamines

(整期优先)网络出版时间:2005-05-15
/ 1
Twocystine-bearing1,3-bridgedcalix[4]areneswereusedasthecoatingsofthequartzcrystalmicrobalance(QCM)withgoldelectrodes.Thetwocalix[4]arenederivativeswereself-assembledontothegoldelectrodesurfacebythecovalentattachmentbetweenthedi-sulfurandgold.Thecompoundofcystine-bearingbi-phenylalanine1,3-bridgedcalix[4]arene(CPC)withlongeralkylchainhadbetterself-assembledcapacityontothefreshsurfacesofgoldelectrodethanthatofcystine-bearing1,3-bridgedcalix[4]arene(CC)withcomparablyshorteralkylchain.ThemodifiedQCMsensorswereusedtorecognizethebutylamineisomersingas.TheresultsshowedthattheQCMcoatedwithbothcompoundshadpreferentialaffinityton-butylamine,theni-butylamine,t-butylamineintherangeoflowconcentrations,indicatingthatintherecognitionprocess,thesterichindranceeffectplayedanimportantrolewhenformingcomplexwithguestmolecules.Whentheconcentrationsoftheanalyteswereincreased,thepolarityandthemagnetismofthebutylaminebecamedeterminativefactors.Thereversibilitywasimprovedgreatlyandtheequilibriumtimewasmuchshorterontheself-assembledfilmthanonthefilmobtainedbydroppingcoating.