Improving the detection limit of a capacitive enzyme sensor by means of a diffusion barrier

摘要

A novel method to improve the lower detection limit of enzyme biosensors basing on capacitive EIS (e1ectro1yte-insulator-semiconductor ) structures is proposed. By choosing a suitable working buffer and introducing a barrier which prevents the analyte from diffusing away from the sensor surface, the detection limit of a penicillin biosensor was lowered by up to three orders of magnitude. Besides, the amount of analyte needed for a single measurement could be decreased from 1 ml to 10μl.