摘要
采用水热法制备巯基乙酸修饰的CdTe量子点,基于链霉素对CdTe量子点同步荧光强度的增强效应,建立一种测定链霉素含量的同步荧光法,并对测定条件如缓冲溶液pH值、量子点浓度和反应时间进行优化。样品经甲醇超声提取后,加入含1.0mL CdTe量子点溶液(3.5×10^(-5) mol/L)和1.0mL Tris—HCl缓冲溶液(pH=6.0)的溶液中,室温反应10min后,测定反应体系在345nm处的同步荧光强度(Δλ=230nm)。结果表明,链霉素浓度在5.0×10-7~1.0×10^(-5) mol/L时与体系相对同步荧光强度存在良好的线性关系,相关系数为0.999 7,检出限为1.0×10^(-8) mol/L。该方法操作简单、快速、灵敏度高,可用于番茄样品中链霉素残留的测定。
Thioglycolic acid capped CdTe quantum dots （QDs） was prepared via hydrothermal synthesis method. Based on the synchro nous fluorescence enhancement of CdTe QDs in the presence o5 strep tomycin, a synchronous fluorescence method for the determination of streptomycin residue was established, Influence factors including pH value of buffer solution, concentration of CdTe QDs and reaction time were investigated. The samples were extracted with methanol by ultrasonic processing, and were added into the solution which was composed of 1.0 mL of CdTe quantum dots （3.5 × 10 -5mol/L） and 1.0 mL of Tris HCI buffer solution （pH=6.0）. After standing for 10 min, the synchronous fluorescence intensity were measured at 345 nm （△λ=230 nm）. The relative synchronous fluorescence inten sity showed good lined relationship to streptomycin concentration in the range of 5.0×10 7--1.0× 10 5 mol/L with the correlation coef- ficient of 0. 999 7. The detection limit was 1.0 × 10 -8 mol/L. With the advantages of simple, rapid and high sensitivity, the proposed method can be used in the determination of streptomycin residue in tomatoes samples.
出处
《食品与机械》
CSCD
北大核心
2016年第3期65-68,164,共5页
Food and Machinery
基金
国家科技支撑计划(编号:2013BAK06B07)
辽宁省教育厅科学研究项目(编号:L2013138)
关键词
CDTE量子点
链霉素
同步荧光法
番茄
CdTe quantum dots
streptomycin residue
synchronousfluorescence method
tomatoes
