Self-charging half-cell biocapacitor utilizing short-circuit current for enhanced sensitivity and simplified...

This study demonstrates for the first time the operational principle of a highly sensitive half-cell enzymatic self-charging biocapacitor that utilizes short-circuit current in glucose detection. The sensor consists of two electrodes: flavin adenine dinucleotide-dependent glucose dehydrogenase/mediator-modified electrode and a Ag/AgCl electrode. When these electrodes are disconnected in an aqueous solution containing glucose (as a model analyte), charge accumulates over time due to the potential difference between the electrodes. Upon reconnecting the electrodes (short-circuiting), a discharge current is generated, which depends on the glucose concentration and the charging time. Notably, the detection limit of this glucose sensor reached 0.092 μM with a 5-min charging time. This work introduces an innovative approach to electrochemical sensing with significant ultrasensitive analyte detection.