Département de chimie moléculaire

Conductometric microbiosensors for the detn. of trypsin were elaborated via the modification of microfabricated interdigitated gold electrodes by a crosslinked urease/BSA coating covered by a gelatin film. The resulting microelectrodes were exposed to different trypsin concns. ranging from 100 pg/mL to 1 mg/mL (1 mU/mL to 10,000 U/mL) for selective proteolytic degrdn. of the gelatin film. Then, the conductometric response of the microbiosensors to urea (33 $μ$M) was recorded as a function of the trypsin concn., the gelatin amt. (8-80 ng) and the incubation time (40 s, 100 min). The optimum incubation time for each trypsin concn. was detd. leading to a detection limit of 100 pg/mL (1 mU/mL). In these optimized conditions, the proof of concept of this sensitive, disposable, low-cost and label-free trypsin biosensors based on a conductometric transducer was demonstrated for the first time. [on SciFinder(R)]