异硫氰酸荧光素-牛血清蛋白-Pb^(2+)“开关”型荧光探针测定尿液中胰蛋白酶  

A Novel Fluorescent Assay for Detection of Trypsin Based on Fluorescein Isothiocyanate-Bovine Serum Albumin-Pb^(2+) Probe

作　　者：刘长青 廖秀芬 陶慧林[2] 孙超[2] 徐杰[2] 

机构地区：[1]青海省有色地质矿产勘查局地质矿产勘查院测试中心,青海西宁810006 [2]桂林理工大学化学与生物工程学院,广西桂林541004

出　　处：《分析科学学报》2016年第1期79-83,共5页Journal of Analytical Science

基　　金：广西矿冶与环境科学实验中心资助项目(No.KH2012ZD008)

摘　　要：本文研究了"开关"型异硫氰酸荧光素(FITC)-牛血清蛋白(BSA)-Pb2+荧光探针测定胰蛋白酶。实验发现,FITC-BSA探针在Pb2+和十二烷基苯磺酸钠(DBS)存在下,可以发出较强的荧光,此时体系处于"打开"状态。当在pH=7.8的Tris-HCl缓冲溶液中加入胰蛋白酶后,FITC-BSA-Pb2+发生荧光猝灭,探针被"关闭",并且胰蛋白酶的浓度在一定范围内与探针的荧光猝灭程度呈良好的线性关系。实验表明,胰蛋白酶浓度与体系荧光猝灭程度在2.4~24μg/mL间呈良好线性关系,相关系数r=0.9972,方法检出限(3σ/k)为0.80μg/mL。该方法应用于尿液中胰蛋白酶的检测,其相对标准偏差(RSD)≤3.0%,回收率范围为102.1%~106.0%。In this paper,a fluorescence assay for detection of trypsin has been established based on fluorescence quencheing of fluorescein isothiocyanate-bovine serum albumin-Pb2＋（FITC-BSA-Pb2＋）probe.It was found that Pb2＋could enhance the fluorescence of FITC-BSA system,which made the probe more active and in a ＂turn on＂ state.While upon the introduction of trypsin,fluorescence quenching of FITC-BSAPb2＋probe occurred,the probe thus was ＂turn off＂.Experimental results show that,in Tris-HCl buffer solution at pH =7.8,the quenched fluorescence of FITC-BSA-Pb2＋is linearly proportional to the concentration of trypsin within the range of 2.4-24μg/mL,with a detection limit of 0.8μg/mL（n=11）.The proposed fluorescence probe has been successfully applied in detection of trypsin in urine samples via standard addition method,and the recovery rate obtained was 102.1%-106.0%,RSD≤3.0%,indicating its potential for diagnostic purpose.

关 键 词：异硫氰酸荧光素-牛血清蛋白-Pb^2+ 胰蛋白酶 “开关”型荧光探针 

分 类 号：O657.39[理学—分析化学]