免疫纳米金催化氯金酸-盐酸羟胺光度法检测免疫球蛋白G  

Immunonanogold Catalytic Spectrophotometric Determination of Trace IgG

作　　者：邓俊耀[1,2] 张声森[1] 蒋治良[1,3] 

机构地区：[1]广西师范大学环境与资源学院,广西桂林541004 [2]桂林市妇幼保健院,广西桂林541001 [3]桂林工学院材料与化学工程系,广西桂林541004

出　　处：《光谱学与光谱分析》2008年第12期2935-2938,共4页Spectroscopy and Spectral Analysis

基　　金：国家自然科学基金项目(20667001);广西自然科学基金项目(0728213);广西新世纪十百千人才基金项目资助

摘　　要：在pH 2.27的柠檬酸钠-盐酸缓冲溶液中,纳米金对氯金酸-盐酸羟胺生成较大粒径金颗粒这一慢反应具有较强的催化作用。较大粒径金颗粒在600-1000 nm处有一个较宽的吸收峰。将纳米金标记羊抗人IgG获得免疫纳米金,免疫纳米金也具有相同催化效果。在一定条件下,金标记羊抗人IgG与IgG发生特异性结合生成纳米金免疫复合物。以16000 rpm速度离心分离获得未反应的纳米金标抗上层溶液。以它作为催化剂催化氯金酸-盐酸羟胺微粒反应,700 nm处的吸光度A700 nm线性降低。其降低值ΔA700 nm与IgG在0.1-10 ng·mL^-1范围内呈良好线性关系,检出限为0.06 ng·mL^-1。本法具有灵敏、快速和较高的特异性,用于定量分析人血清IgG,结果满意。Gold nanoparticles the size of about 10 nm were prepared by improved trisodium citrate reduction procedure,and were used to label goat anti-human IgG to obtain a sensitive spectral probe for IgG in the condition of pH 6.5.The immune reaction of nanogold-labeled IgG antibody（anti-IgG） with the antigen IgG took place to form the nanogold immune complex in pH 7.0 Na2HPO4-C6H8O7 buffer solution and in the presence of polyethylene（PEG）.The optimal immunoreaction conditions were pH 7.0,10.76 μg·mL1 nanogold-labeled anti-IgG,8.0% PEG 6000 and incubation time of 30 min under the ultrasonic irradiation.After centrifuging for 15 min at 16 000 rpm,the excess nanogold-labeled anti-IgG in the upper solutions was obtained,and was used to catalyze the colored particle reaction of HAuCl4 with NH2OH·HCl to produce gold particles with bigger size.The influence of pH value,HAuCl4 and NH2OH·HCl concentration,and reaction temperature and time on the immunonanogold catalytic reaction was considered spectrophotometrically.A pH 2.27 Na3C6H5O7-HCl buffer solution,0.094 mmol·L HAuCl4, 1.92 mmol·L NH2OH·HCl,and reaction time of 6 min at 30 ℃ water bath were chosen for use.Results demonstrated that with increasing IgG,the concentration of gold labeled anti-IgG in the upper solution decreased,and the absorbance decreased linearly.Linear relationships between the decreased absorbance at 700 nm and the IgG concentration CIgG in the range of 0.10-10 ng·mL^-1 were obtained.Its regress equation was ΔA760 nm=0.014 4cIgG＋0.004 2,the related coefficient was 0.992 6,and the detection limit reached 0.06 ng·mL^-1IgG.The influence of foreign substances on the determination of 3 ng·mL^-1IgG was examined,with the relative error ±10%.Results showed that the following coexistent substances had no impact on the assay： 6 000 ng·mL^-1HSA,6 000 ng·mL^-1gluocose,6 000 ng·mL^-1Zn（Ⅱ）,3 000 ng·mL^-1 IgA,3 000 ng·mL^-1 Ca（Ⅱ）,3 000 ng·mL^-1 L-arginine,3 000 ng·mL^-1 β-phenylalanine,2 400 ng·mL^-1Cu（Ⅱ）,2 400 ng·mL^

关 键 词：免疫球蛋白G 免疫纳米金 纳米金催化 光度法 

分 类 号：O657.3[理学—分析化学]