College of Chemistry and Chemical Engineering, Central South University, Changsha 410083, China; Shandong Provincial Key Laboratory of Life-organic Analysis, College of Chemistry and Chemical Engineering, Qufu Normal University, Qufu, Shandong 273165, China.
Department of Surgery, The Second Xiang-ya Hospital, Central South University, Changsha 410011, China.
Biosens Bioelectron. 2011 May 15;26(9):3927-31. doi: 10.1016/j.bios.2011.03.013. Epub 2011 Mar 21.
A new colorimetric immunoassay for the detection of cancer biomarker prostate specific antigen (PSA) was developed based on the intrinsic peroxidase activity of graphene oxide (GO). GO can catalyze the reaction of hydroquinone in the presence of H2O2 to produce a brown color solution. Secondary antibody (Ab2) functionalized GO (GO-Ab2) was used as label for the immunoassay, while magnetic bead (MB) was selected to immobilize primary anti-PSA antibody (Ab1). In the presence of PSA, an immunocomplex, sandwiching the antigen protein, is formed between the GO-Ab2 and MB-Ab1. With the separation of the immunocomplex using an external magnetic field, different amounts of GO-Ab2 in the solution were mixed with hydroquinone and H2O2 solution and displaying colors. Different colors corresponding to different concentrations of PSA can be directly detected with eyes. Such a simple immunoassay holds great potential as sensitive, selective and point-of-care (POC) tool for clinical diagnosis of cancer biomarkers.
基于氧化石墨烯（GO）的固有过氧化物酶活性，开发了一种用于检测癌症生物标志物前列腺特异性抗原（PSA）的新型比色免疫分析方法。GO 可以在 H2O2 的存在下催化对苯二酚的反应，生成棕色溶液。功能化的二级抗体（Ab2）的 GO（GO-Ab2）被用作免疫分析的标记物，而磁珠（MB）被选择用于固定一级抗 PSA 抗体（Ab1）。在 PSA 存在下，GO-Ab2 和 MB-Ab1 之间形成夹抗原蛋白的免疫复合物。通过外部磁场分离免疫复合物后，将溶液中不同量的 GO-Ab2 与对苯二酚和 H2O2 溶液混合并显色。不同颜色对应于不同浓度的 PSA 可以直接用眼睛检测。这种简单的免疫分析方法具有很大的潜力，可作为癌症生物标志物临床诊断的灵敏、选择性和即时检测（POC）工具。
