Pal Mintu, Khan Raju
Biotechnology Group, Biological Sciences and Technology Division, CSIR-North East Institute of Science & Technology, Academy of Scientific and Innovative Research, Jorhat, 785006, Assam, India.
Analytical Chemistry Group, Chemical Sciences and Technology Division, CSIR-North East Institute of Science & Technology, Academy of Scientific and Innovative Research, Jorhat, 785006, Assam, India.
Anal Biochem. 2017 Nov 1;536:51-58. doi: 10.1016/j.ab.2017.08.001. Epub 2017 Aug 5.
In this work, we report a novel electrochemical immunosensor based on gold nanoparticles deposited on the surface of graphene oxide layers and was used for immobilization of monoclonal anti-PSA antibody via EDC/NHS coupling method to detect prostate-specific antigen (PSA), a valuable biomarker for early detection of prostate cancer. To confirm the functionality of the antibody, we performed immunofluorescence staining using human prostate adenocarcinoma cells, LNCaP. Scanning Electron Microscopy (SEM), cyclic voltammetry, and other electrochemical techniques were used to characterize the resulting electrode surface. Unlike the previous research, this novel immunosensor functions very well with a low detection limit of 0.24 fgmL at signal to noise ratio of 3; furthermore, it exhibits a significantly increased electron transfer and high sensitivity of 5.4 μA fgmL with regression coefficient (R = 0.99) toward PSA. The immunosensor was verified for selective and accurate detection of PSA in human serum with recovery of 97.67%. Overall, data suggested that our developed biosensor holds great promise as a useful alternative diagnostic tool for the detection of different cancer biomarkers, in particular PSA present in biological samples.
在本研究中，我们报道了一种新型电化学免疫传感器，该传感器基于沉积在氧化石墨烯层表面的金纳米颗粒，并通过1-乙基-3-(3-二甲基氨基丙基)碳二亚胺/ N-羟基琥珀酰亚胺（EDC/NHS）偶联方法用于固定单克隆抗前列腺特异性抗原（PSA）抗体，以检测前列腺特异性抗原（PSA），这是一种用于早期检测前列腺癌的重要生物标志物。为了确认抗体的功能，我们使用人前列腺腺癌细胞LNCaP进行了免疫荧光染色。利用扫描电子显微镜（SEM）、循环伏安法和其他电化学技术对所得电极表面进行了表征。与先前的研究不同，这种新型免疫传感器性能良好，在信噪比为3时检测限低至0.24 fg/mL；此外，它的电子转移显著增加，对PSA的灵敏度高达5.4 μA/fg/mL，回归系数（R = 0.99）。该免疫传感器经证实可选择性、准确地检测人血清中的PSA，回收率为97.67%。总体而言，数据表明我们开发的生物传感器作为一种检测不同癌症生物标志物，特别是生物样品中PSA的有用替代诊断工具具有很大的前景。
