Chen Huan, Jiang Jian-Hui, Li Yin-Feng, Deng Ting, Shen Guo-Li, Yu Ru-Qin
State Key Laboratory of Chem/Biosensing and Chemometrics, Chemistry and Chemical Engineering College, Hunan University, Changsha 410082, China.
Biosens Bioelectron. 2007 Jan 15;22(6):993-9. doi: 10.1016/j.bios.2006.04.015. Epub 2006 May 24.
A simple rapid piezoelectric immunoagglutination assay (PEIA) technique with antibody-modified liposome has been developed for direct quantitative detection of human immunoglobulin G (hIgG). This technique is based on specific agglutination of antibody-coated liposome particles in the presence of the corresponding antigen, which can be monitored by the frequency shift of a piezoelectric device. Compared with conventional piezoelectric assays, this liposome-based PEIA does not require the immobilization of antigen or antibody on the quartz crystal surface, making the developed technique especially useful for rapid and renewable immunochemical determination. To alleviate non-specific adsorption of serum proteins, modification of the quartz crystal surface by different protocols and the composition of the assay medium have been investigated. The results indicate that the background interference can be substantially minimized through modifying the quartz crystal surface with a bovine serum albumin (BSA) layer and introducing an appropriate amount of BSA in the assay medium. The effects of the liposome composition, the liposome concentration and the concentration of poly(ethylene glycol) (PEG) in the assay medium, have also been investigated. The frequency responses of the liposome-based PEIA are linearly correlated to hIgG concentration in the range of 0.05-6 microg mL(-1) with a detection limit of 50 ng mL(-1).
已开发出一种采用抗体修饰脂质体的简单快速压电免疫凝集测定法（PEIA）技术，用于直接定量检测人免疫球蛋白G（hIgG）。该技术基于在相应抗原存在下抗体包被的脂质体颗粒的特异性凝集，这可通过压电器件的频率偏移进行监测。与传统的压电测定法相比，这种基于脂质体的PEIA不需要将抗原或抗体固定在石英晶体表面，使得所开发的技术对于快速和可再生免疫化学测定特别有用。为了减轻血清蛋白的非特异性吸附，已研究了通过不同方案对石英晶体表面进行修饰以及测定介质的组成。结果表明，通过用牛血清白蛋白（BSA）层修饰石英晶体表面并在测定介质中引入适量的BSA，可将背景干扰大幅降至最低。还研究了脂质体组成、脂质体浓度以及测定介质中聚乙二醇（PEG）浓度的影响。基于脂质体的PEIA的频率响应与hIgG浓度在0.05 - 6μg mL(-1)范围内呈线性相关，检测限为50 ng mL(-1)。
