Biopolymers and cell. 2008; 24 (6): 494 - 502

Optimization of multibiosensor operation for inhibitory analysis of toxins

O. O. Soldatkin, O. S. Pavluchenko, O. L. Kukla, V. M. Arkhypova, S. V. Dzyadevych, O. P. Soldatkin, A. V. El’skaya

The operation of highly sensitive and selective multibiosensor based on different immobilized enzymes as bioselective elements and the matrix of pH-sensitive field effect transistors as transducers has been investigated. To develop bioselective elements of multibiosensor, the enzymes acetylcholinesterase, butyryl- cholinesterase, urease, glucose oxidase, and three-enzyme system invertase-mutarotase-glucose oxidase with high sensitivity to toxins were used. The optimal concentrations of substrates for inhibitory analysis application were chosen as follows: 10 mM acetylcholine, 5 mM butyrylcholine, 5 mM urea, 5 mM sucrose, and 2 mM glucose. The incubation time of multibiosensor in toxic solution was 20 min. No cross-influence of substrates in all the enzyme systems used was found. The inhibitory influence of separate toxins and their mixture on the bioselective elements of multibiosensor was studied.

Keywords: multibiosensor, immobilized enzymes, pH-sensitive field-effecttransistors, glucose, inhibitory analysis, toxins.