Detection of carbohydrate antigen 19-9 by a diamond solution-gate field-effect transistor sensor

摘要

Detection of carbohydrate antigen 19-9 (CA19-9) via hydrogen-terminated diamond (H-diamond) solution-gate field-effect transistor (SGFET) sensor had been carried out for the first time. Linker molecule 1-pyrenebutyric acid-N-hydroxy succinimide ester (Pyr-NHS) was fixed on the surface of H-diamond by pi-pi bonding. Then, anti-CA19-9 antibody was immobilized with Pyr-NHS. After specific binding of CA19-9 and antibody, transfer characteristics of H-diamond SGFET exhibited a gate voltage shift in negative direction at the same output current. The sensitivity of sensor was obtained as -50.98 mV/Log(10)antigen concentration. The minimum detection concentration was 0.001 U/mL. This article illustrated a potential application of H-diamond SGFET sensor in CA19-9 detection.