Département de chimie moléculaire

An attractive biocomposite based on polycryst. bismuth oxide (BiOx) film and polyphenol oxidase (PPO) was proposed for the construction of a mediator-free amperometric biosensor for phenolic compds. in environmental water samples. The phenolic biosensor could be easily achieved by casting the biocomposite on the surface of glassy carbon electrode (GCE) via the crosslinking step by glutaraldehyde. The lab.-prepd. bismuth oxide semiconductor was polymorph. Its hydrophilicity provided a favorable microenvironment for retaining the biol. activity of the immobilized protein. The parameters of the fabrication process and the various exptl. variables for the enzyme electrode were optimized. The proposed PPO/BiOx biosensor provided a linear response to catechol over a concn. range of 4 × 10-9 M to 1.5 × 10-5 M with a dramatically developed sensitivity of 11.3 A M-1 cm-2 and a detection limit of 1 × 10-9 M based on S/N = 3. In addn., the PPO/BiOx biocomposite was characterized by SEM, FTIR, and rotating disk electrode voltammetry. [on SciFinder(R)]