采用超灵敏磷光传感器测定痕量咖啡因  

Determination of Trace Caffeine Based on Ultra-Sensitive Phosphorescent Sensor

作　　者：饶滢 庄国顺[2] RAO Ying;ZHUANG Guoshun(Department of Clinical Medicine,Zhangzhou Vocational Health College,Zhangzhou 363000,China;Department of Environmental Science and Engineering,Fudan University,Shanghai 200433,China)

机构地区：[1]漳州卫生职业学院临床医学系,福建漳州363000 [2]复旦大学环境科学与工程系,上海200433

出　　处：《三明学院学报》2022年第6期47-59,共13页Journal of Sanming University

摘　　要：发现水溶性多壁碳纳米管(MWNTs’)-牛血清蛋白(BSA)中BSA分子的-NH2可与异硫氰酸荧光素(FITC)分子中的异硫氰酸基团(-NCS)作用生成了异硫氰酸基团-牛血清蛋白-水溶性多壁碳纳米管(FITC-BSA–MWNTs’),使FITC共轭体系中碳原子上的π电子密度(δ)增大而发射FITC的较强室温磷光(RTP)。质子化的咖啡因(CF+)与FITC-BSA–MWNTs’中FITC分子的带负电荷羧基(-COO-)发生静电吸附作用而生成质子化的咖啡因·异硫氰酸基团-牛血清蛋白-水溶性多壁碳纳米管离子缔合物([CF]+·[FITC-BSA-MWNTs’]-),使FITC分子共轭体系中碳原子上的π电子密度降低,导致FITC的RTP信号剧烈猝灭,据此建立了[CF]+·[FITC-BSA-MWNTs’]-离子缔合物FITC的电子效应磷光传感器测定痕量咖啡因(CF)的新方法,同时探讨了其分析应用与反应机理。It was found that the-NH2group of bovine serum albumin(BSA)in water-soluble multi-walled carbon nanotubes(MWNTs’)-BSA could react with the-NCS group of fluorescein isothiocyanate(FITC)to form compound(FITC-BSA-MWNTs’),which increased theπ-electron density(δ)of carbon atom in FITC conjugated system and emitted strong room temperature phosphorescence(RTP)of FITC.More interestingly,the electrostatic adsorption between the-COO-group of FITC molecule in FITC-BSA-MWNTs’and the protonated caffeine(CF+)lead to the formation of an ion association complex[CF]+·[FITC-BSA-MWNTs’]-,which result in the decrease in theδof the carbon atom in the FITC conjugated system and the rapid quench of the RTP signal of FITC molecule.Its analytical application and reaction mechanism were also discussed.

关 键 词：咖啡因 π电子效应 多壁碳纳米管 异硫氰酸荧光素 磷光传感器 

分 类 号：O656[理学—分析化学]