College of Chemistry and Chemical Engineering, Yangzhou University, Jiangsu Key Laboratory of Environmental Engineering and Monitoring, Yangzhou 225002, PR China.
Anal Chim Acta. 2013 Apr 24;774:85-91. doi: 10.1016/j.aca.2013.02.041. Epub 2013 Mar 15.
An ultrasensitive chemiluminescent (CL) immunoassay system was developed for the detection of tumor marker. This sandwich CL assay method was for the first time designed based on a highly efficient streptavidin-functionalized multi-walled carbon nanotubes (MWCNTs) platform. The glass slide was firstly silylanized with 3-gycidoxypropyltrimethoxysilane (GPTMS) to generate surface epoxy group functionality. Subsequently, the MWCNTs/chitosan solution was mixed with streptavidin solution, and a certain amount of the resulting suspension was dropped on the surface of the epoxy-activated glass substrate to form a firm streptavidin-functionalized MWCNTs platform. The biofunctionalized-MWCNTs platform shows large reactive surface area and excellent biocompatibility. The capture antibody can be efficiently immobilized on the biosensing platform surface based on the highly selective recognition of streptavidin to biotinylated antibody. Using α-fetoprotein (AFP) as model analyte, the proposed method exhibits wide linear range of 0.001-0.1 ng mL(-1) with a low detection limit down to 0.52 pg mL(-1). The CL immunoassay system displays 7.9-fold increase in the detection sensitivity compared to the immunosensor without using MWCNTs. Moreover, the resulting immunosensor demonstrates excellent specificity, good reproducibility, and acceptable stability. This streptavidin-functionalized MWCNTs platform opens a novel and promising avenue for fabricating ultrasensitive CL immunoassay system.
建立了一种用于检测肿瘤标志物的超灵敏化学发光（CL）免疫分析系统。首次基于高效的链霉亲和素功能化多壁碳纳米管（MWCNTs）平台设计了这种三明治 CL 测定方法。首先用 3-缩水甘油丙基三甲氧基硅烷（GPTMS）对载玻片进行硅烷化处理，以生成表面环氧基团功能。随后，将 MWCNTs/壳聚糖溶液与链霉亲和素溶液混合，将一定量的所得悬浮液滴加到环氧活化玻璃基底的表面上，以形成牢固的链霉亲和素功能化 MWCNTs 平台。生物功能化-MWCNTs 平台具有较大的反应表面积和优异的生物相容性。基于链霉亲和素对生物素化抗体的高度选择性识别，捕获抗体可以有效地固定在生物传感平台表面上。以甲胎蛋白（AFP）为模型分析物，所提出的方法在 0.001-0.1ng mL(-1)的宽线性范围内表现出较低的检测限，低至 0.52pg mL(-1)。与不使用 MWCNTs 的免疫传感器相比，CL 免疫分析系统的检测灵敏度提高了 7.9 倍。此外，所得免疫传感器表现出优异的特异性、良好的重现性和可接受的稳定性。这种链霉亲和素功能化 MWCNTs 平台为制备超灵敏 CL 免疫分析系统开辟了一条新颖而有前途的途径。
