摘要
在水相中,分别合成了巯基乙酸为稳定剂的CdTe量子点和超顺磁性纳米Fe3O4,然后将其加入到一定比例的环己烷、Triton-X-100和正硅酸乙酯(TEOS)形成的反相微乳液体系,在恒温30℃时搅拌反应48h后,合成了粒径分布在15～20nm,同时具有荧光和磁性的双功能亲水性复合纳米材料(MQDs).用5%的戊二醛为交联剂,振荡交联1h后,在MQDs表面固定了葡萄糖氧化酶(GOx).固定化GOx的最适pH为5.5,最适温度为21℃,和游离酶不同.基于GOx催化葡萄糖产生H2O2能够引起量子点荧光的淬灭,利用MQDs的磁性及荧光,实现了对样品中葡萄糖的同时分离和可视化荧光检测.
Mercaptoacetic acid capped CdTe quantum dots and superparamagnetic nano Fe3O4 were prepared in the aqueous phase.Next,CdTe and Fe3O4 were added into a reverse microemulsion system through a certain proportion of cyclohexane,Triton-X-100 and TEOS,formed both fluorescent and magnetic bifunctional hydrophilic composite nano-materials （MQDs） after stirring 48 h at 30 ℃.Their uniform distribution of particle sizes were about 15～20 nm.Glucose oxidase （GOx） was immobilized on the surface of MQDs with crosslinking 1 h by 5% glutaraldehyde as crosslinking agent.Compared with free GOx,the optimum pH of immobilized GOx is 5.5 and the optimum temperature was 21 ℃.Using magnetisim and fluorescence of the MQDs,the simultaneous separation and fluorescence visualization detection of glucose were achieved for the samples,based on fluorescence of QDs can be quenched by the H2O2 produced by the GOx catalysis glucose.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2010年第20期2063-2068,共6页
Acta Chimica Sinica
基金
四川省教育厅自然科学科研重点(No.2005A033)
四川农业大学"双支计划"基金资助项目
关键词
量子点
磁性
反相微乳液法
葡萄糖
检测
quantum dots
magnetisim
reverse microemulsion system
glucose
detection
