Nanochemistry and biotechnology

Potentiometric enzyme biosensor modified with gold nanoparticles
Shkotova L.V.1, Zinchenko O.A.1, Soldatkin O.P.1,2
1 Laboratory of Biomolecular Electronics, Institute of Molecular Biology and Genetics, NAS of Ukraine, 150, Akademika Zabolotnogo Str., Kyiv-03680, Ukraine. 
E-mail: luda_shkotova@yahoo.com
2 Institute of High Technologies, Taras Shevchenko National University of Kyiv
2, korp.5, Pr. Akademika Hlushkova, Kyiv-03022, Ukraine.

A highly sensitive, selective potentiometric biosensor based on immobilized butyrylcholinesterase was developed, its laboratory prototype was created. The enzyme served as a sensitive element and pH-sensitive field-effect transistors (FETs) were used as the transducers of a biochemical signal into electric.
Because butyrylcholinesterase has been already used to develop the sensors for determination of heavy metals, organophosphorus/carbamate pesticides and steroidal glycoalkaloids, the present study has been focused on the investigation and adjustment of specificity and sensitivity of the potentiometric biosensor exactly for the case of using gold nanoparticles.
The composition of a butyrylcholinesterase-based bioselective membrane with gold nanoparticles was optimized. Optimal conditions of the biosensor functioning, such as pH and ionic strength of the working buffer solution, were selected. The signal reproducibility of the developed biosensor and its storage stability were studied.