Ultratrace Detection towards Co2+ Ion at Surface of SiO2 Nanoparticles Based on Fluorescence Resonance Energy Transfer
This paper reports a resonance energy transfer-amplifying fluorescence quenching at the surface of silica nanoparticles for the ultrasensitive and ultratrace detection of Co2+ ion in solution.Fluorescence dye and organic amine were covalently modified onto the surface of silica nanopartieles to form a hybrid monolayer of dye fluorophores and amine ligands.The fluorescent silica particles can specifically Co2+ ion species by the charge-transfer complexing interaction between electron-rich amine ligands and electron-deficient Co2+ ion.The resultant C02+-amine complexes bound at the silica surface can strongly suppress the fluorescence emission of the chosen dye by the fluorescence resonance energy transfer (FRET) from dye donor to the irradiative C02+-atnine acceptor through intermolecular polar-polar interactions at spatial proximity.The quenching efficiency of the hybrid nanoparticles with Co2+ is greatly amplified by at least 10 folds that of the corresponding pure dye.The nanoparticle-assembled arrays on silicon wafer can sensitively detect down to ~lnM Co2+ with the use of only 10μL of solution (~60pg Co2+).The simple FRET-based nanoparticle sensors reported here exhibit a high and stable fluorescence brightness,strong analyte affinity and good assembly flexibility,and can thus find many applications in the detection of ultratrace analytes.
fluorescence resonance energy transfer silica nanoparticle molecular recognition ultratrace detection Co2+ ion
GAO Darning SUN Hong SI Jingyu CHEN Hong ZHU Dechun SHI Jianjtm
Department of Chemistry and Materials Engineering, Hefei University;Sino-German Research Center for Department of Chemistry and Materials Engineering, Hefei University
国际会议
合肥
英文
618-624
2012-05-24（万方平台首次上网日期，不代表论文的发表时间）