▎ 摘　　要

In this study, the combination of novel valinomycin doped chitosan-graphene oxide (C-GO-V) thin film and surface plasmon resonance (SPR) system for potassium ion (K+) detection has been developed. The novel C-GO-V thin film was deposited on the gold surface using spin coating technique. The system was used to monitor SPR signal for K+ in solution with and without C-GO-V thin film. The K+ can be detected by measuring the SPR signal when C-GO-V thin film is exposed to K+ in solution. The sensor produces a linear response for K+ ion up to 100 ppm with sensitivity and detection limit of 0.00948 degrees ppm(-1) and 0.001 ppm, respectively. These results indicate that the C-GO-V film is high potential as a sensor element for K+ that has been proved by the SPR measurement. (C) 2017 Elsevier B.V. All rights reserved.