Bimetallic cerium and ferric oxides nanoparticles embedded within mesoporous carbon matrix: Electrochemical immunosensor for sensitive detection of carbohydrate antigen 19-9

Publication date: Available online 11 April 2019Source: Biosensors and BioelectronicsAuthor(s): Minghua Wang, Mengyao Hu, Bin Hu, Chuanpan Guo, Yingpan Song, Qiaojuan Jia, Linghao He, Zhihong Zhang, Shaoming FangAbstractA label-free electrochemical immunosensor was successfully developed for sensitively detecting carbohydrate antigen 19–9 (CA19-9) as a cancer marker. To achieve this, a series of bimetallic cerium and ferric oxide nanoparticles embedded within the mesoporous carbon matrix (represented by CeO2/FeOx@mC) was obtained from the bimetallic CeFe-based metal organic framework (CeFe-MOF) by calcination at different high temperatures. The formed CeO2 or FeOx nanoparticles were uniformly distributed within the highly graphitized mesoporous carbon matrix at the calcination temperature of 500 °C (represented by CeO2/FeOx@mC500). However, the obtained nanoparticles were aggregated into large size when calcined at the temperatures of 700 and 900 °C. The CA 19–9 antibody can be anchored to the CeO2/FeOx@mC network through chemical absorption between carboxylic groups of antibody and CeO2 or FeOx by ester-like bridging. The CeO2/FeOx@mC500-based immunosensor displayed superior sensing performance to the pristine CeFe-MOF, CeO2/FeOx@mC700- and CeO2/FeOx@mC900-based ones. Electrochemical impedance spectroscopy results showed that the developed immunosensor exhibited an extremely low detection limit of 10 μU·mL−1 (S/N = 3) within a wide range from 0.1 mU·mL−1...
Source: Biosensors and Bioelectronics - Category: Biotechnology Source Type: research