基于杂交链式反应的可视化免疫分析检测癌胚抗原

Colorimetric immunoassay based on hybrid chain reaction for detection of tumor marker

构建了基于杂交链反应的比色免疫分析方法,实现了对肿瘤标志物癌胚抗原的检测。在抗原-抗体的特异性结合作用下,在磁珠表面构建夹心式免疫复合物,进一步结合杂交链式反应(HCR)作为信号放大策略,将染料曙红Y嵌入至DNA长链中。在可见光的照射下,能使反应底液中的四甲基联苯胺(TMB)氧化,发生明显的颜色变化,由无色变为蓝色,且与癌胚抗原的浓度呈正相关性。在最优实验条件下,癌胚抗原的浓度在1 pg/mL^5 ng/mL范围内呈线性变化,检出限为1 pg/mL。

A colorimetric immunoassay based on hybridization chain reaction was constructed for detection of carcinoembryonic antigen.A sandwich immunological complex was constructed on the surface of the magnetic beads under the specific binding of the antigen and antibody.And then the hybridization chain reaction(HCR)was further used as a signal amplification strategy,meanwhile eosin Y was embed into the DNA long chain.Under the irradiation of visible light,the solution had a significant color change from colorless to blue due to the oxidation reaction of tetramethylbenzidine(TMB).And the color depth was positively correlated with the concentration of carcinoembryonic antigen.Under optimal experimental conditions,the concentration of carcinoembryonic antigen showed a linear relationhip from 1 pg/mL to 5 ng/mL with a detection limit of 1 pg/mL.