Nanochemistry and biotechnology

Using zeolites for improvement of performance of biosensor based on ISFET for inhibitory determination of toxic compounds 
Soldatkin O.O.1, Soy E.2, Arkhypova V.1, Pyeshkova V.1, Akata B.2, Soldatkin A.P.1, Dzyadevych S.1

1 Institute of Molecular Biology and Genetics of NAS of Ukraine, Zabolotnogo Street 150, 03143 Kyiv, Ukraine. 
E-mail: alex_sold@yahoo.com 

2 Micro and Nanotechnology Department, Central Laboratory, Middle East Technical University, 06530 Ankara, Turkey

Immobilization of biological material is a problem of prime importance for the biosensor creation. Successful immobilization directly influences key characteristics of biosensors (activity of biological material, linear working range, sensitivity to substrate, reproducibility and operational stability of signals, duration of storage, etc.). Therefore, selection of main parameters of the immobilization process is an essential challenge in the development of biosensors. In particular, an improvement of the methods of biomembrane immobilization onto the sensing elementis an important task.
A number of potentiometric biosensors based on coimmobilization of enzymes with different types of zeolite on pH-ISFET have been developed for inhibitory determination of toxic compounds. Their working characteristics have been determined and compared. It was shown that some of modification of the zeolite BEA crystals can improve analytical characteristics of potentiometric biosensors for detection of toxic substances.
These results show that it is possible to regulate the ISFET characteristics for different enzyme-based biosensors by tailoring the electrode surfaces via different zeolites. This makes zeolites strong candidates for integration into biosensors as ISFET modifiers.
The work was carried out thanks to financial support from the National Research Fund of Ukraine in the framework of the competition of projects for research and development "Support of research of leading and young scientists". Also this study is part of a project that has received funding from the European Union’s Horizon 2020 research and innovation programme under the grant agreement No 958491, Project Waste2Fresh .