Biosensor based on screen-printed electrodes modified with glucose oxidase and γ-amylase for determination of glucose and starch in fermentation media

Kamanin S. S., Arlyapov V. A.

Tula State University

Alcoholic fermentation is used in the production process of alcoholic beverages and breadmaking technology. In alcohol production the feedstock for fermentation are starchy products: potatoes, corn, rye, millet and others. The amount of starch in the feedstock, and the dynamics of its expenditure in the fermentation process are some of the key performance indicators of the fermentation. A promising approach for the analysis of the starch content is the application of biosensor technology. Research in the field of biosensor detecting open great opportunities for the development of bioanalytical systems, characterized by low cost. Most interesting is the possibility of creating bienzyme biosensor system based on glucose oxidase and γ-amylase, which will allow monitoring of fermentation process and analysis of the quality of starchy feedstock.

This paper presents the results of the development of enzyme biosensor based on screen-printed electrodes for rapid determination of starch and glucose during the fermentation process.

Screen-printed graphite electrodes (Rusens, Russia) and potentiostat EmStat (PalmSens, Netherlands), integrated with a personal computer were used for signal registration. Working electrode was covered with nanolayers of Prussian blue – hydrogen peroxide decomposition catalyst. Signal processing performed via specialized software – PalmSens PStrace.

As a result of the work, modification of screen-printed electrodes with enzymes: glucose oxydase and γ-amylase, immobilized in crosslinked gel of bovine serum albumin, was carried out to allow the selective determination of glucose and starch concentrations in fermentation mass. Main analytical and metrological characteristics of the biosensors based on fabricated electrodes were obtained. Detection range of glucose concentration for biosensor based on screen-printed electrode, modified with glucose oxidase, accounted 0.05-1.1 mM, sensitivity coefficient was 310 nA/mM. Detection range of starch concentration for biosensor based on screen-printed electrode, modified with mixture of glucose oxidase and γ-amylase, accounted 0.03-0.59 g/l, sensitivity coefficient was 640 nA/g·l.

The contents of components in samples of the fermentation mass, taken at different stages of the fermentation process, were determined using the developed biosensor and by reference methods (high performance liquid chromatography and polarimetry). Statistical analysis of the results showed that the values of glucose and starch content, determined using the modified electrodes and the reference methods, differ significantly from each other.

Thus, it was shown that modified screen-printed electrodes can serve as the basis for developing biosensors with high analytical and metrological characteristics that can be used for monitoring fermentation processes and assaying the components of fermentation masses and fermentation products.

The study was supported by the Federal Target Program “Research and Development in Priority Directions of Progress of the Scientific and Technological Complex of Russia for the Years 2014–2020” (agreement no. 14.574.21.0062) and Russian Federation President’s grant for the state support of young Russian scientists - PhD (no. 14.Z56.14.330-MK).