Investigation of bioelectrochemical properties of biomolecules
Investigation of electron transport in biomolecules
Creation of biosensors and bioreactors
Investigation of the mechanism of action of biomolecules and cells in heterogeneous systems and mathematical modeling.
Whole-cell biosensors, bacterial self-organization, biofilms.
RESEARCH OWEREVIEW 2012-2017
Specially prepared carbon materials can possess direct electrochemical communication with redox centers of some redox proteins. For this reason a few types of graphite nanoparticles have been manufactured by oxidation of graphite using different protocols and characterized by AFM, Raman spectroscopy, TGA and BET analysis. Also thermally reduced graphene oxides and nanocomposite materials have been prepared and studied. Different oxidoreductases were applied and demonstrated direct electron transport between surface of the carbon materials and active center of the enzyme. These structures were applied in different technological structures. One of them - creation of mediatorless bio-anodes and bio-cathodes for bio-solar cells, bio-batteries and bio-fuel cells.
Second direction -the same structures were applied for the creation of new type of biosensors for the determination of the sugars and alcohols. Carbon materials were applied for the electrochemical monitoring of urease activity and electrochemical biosensors for urea were developed. These biosensors were applied in medicine, environment control, and for the quality control in food industry. In this field the project „Non- invasive approach to early diagnosis and prognosis of acute severe pancreatitis (AP)” was recently funded. The ambitiousness of the project is to diminish lack of information causing AP diagnostic, prognostic and followed treatment problems by deep understanding of AP biochemical processes that could help to create new diagnostic tools. Beekeeping products conserved with honey were analyzed. Monitoring of the changes of parameters of the mixtures via different storage conditions revealed a stabilizing influence of honey and additives on anti-oxidative properties, composition of flavonoids and activity of the enzymes of the mixtures.
Third direction - the same bio-electro-catalytic system was applied in bioreactors for the selective conversion of substrates into useful products. Conversion of N-hydroxy- compounds, alcohols and other substrates catalysed by oxidoreductases (laccases, peroxidases and quinoprotein dehydrogenases) was investigated. These systems were extended into multi-step synthesis of natural products & analogues involving sequences of enzymes conversion chains.
The numerical mathematical modelling of heterogeneous bio-electro-catalytic systems made possible to determine several structural and kinetic parameters of the sensor and bioreactor construction.
Bioluminescence imaging experiments were carried out to characterize spatiotemporal patterns of self-organization of bioluminescent E. coli and its mutants in standard microtiter plates. An analysis of the effects of mutations shows that spatiotemporal patterns formed due to migration (swimming) of cells near three phase contact line are not related to the chemotaxis system of bacteria. An analysis of experimental data and mathematical modelling of pattern formation indicate that pattern-forming active bacteria can be interpreted as self-phoretic cells dispersed in a liquid suspension.
Department participated in the international sheering of the food quality control knowledge. Food safety and Food safety assessment training courses were translated into Lithuanian language and distributed among food producers. Department participated in the introduction of ES Food safety legislation into food industry system in Turkey.