Development and characterization of MnO2-based electrode for a microfluidic device. Features of use in the study of oxidative stress

Poltavets, V.V. and Maslak, H.S. and Netronina, O.V. (2025) Development and characterization of MnO2-based electrode for a microfluidic device. Features of use in the study of oxidative stress. Українська конференція з міжнародною участю "ХІМІЯ, ФІЗИКА ТА ТЕХНОЛОГІЯ ПОВЕРХОНЬ"присвячено 95-річчю з дня народження Олексія Чуйко, Академік НАН України. p. 34.

Text Тези_4_Полтавець.pdf Download (350kB)

Abstract

Microfluidic systems as a new analytical method have been developed not so long time ago, but their use opens up great prospects [1]. In the development of electrochemical microfluidic biosensors, the formation of working electrodes is important. Main characteristics of such electrodes are mechanical strength, sensitivity and selectivity. We understand oxidative stress as an increase in free radicals, which leads to disruption of redox signal transmission and destruction of molecules. The main relatively stable intermediate of enzyme antioxidant reactions is hydrogen peroxide. Therefore, H2O2 is the main analyte that is fixed in microfluidic devices. MnO2 for working electrode material is selected as a known catalyst for the decomposition of hydrogen peroxide. After a systematic study, it was determined that the maximum catalytic properties of manganese dioxide are obtained using the following formation method. The MnO2 coating was formed by cyclic voltammetry method (CV) in a water solution of 0.005 M MnSO4, 0.5 M Na2SO4 with pH 1 during 30 cycles at the range of potentials 0.65 V – 2.1 V vs. Ag/AgCl/3M KCl and subsequently dried at 60 0C for 12 hours. The sediment was characterized by scanning electron microscopy, electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy. In a microfluidic cell we reproducibly recorded H2O2 concentrations in the range from 0.1 mM to 3 mM. In biochemical studies, blood plasma of laboratory rats was taken in a calm state and in a state of stress. The activity of the enzyme catalase, which decomposes hydrogen peroxide, was studied. The difference in the amount of H2O2 fixed by the electrode when mixing a given amount of peroxide with blood plasma and without mixing was assessed. Thus, we observe the work of the enzyme over time in vitro. None of the known enzymatic analysis methods provides such data. Our current efforts are focused on deciphering the antioxidant activity data of wounded soldiers in collaboration with Dnipro hospitals. This will help adjust treatment and rehabilitation.

Item Type:	Article
Additional Information:	доповідь на конференції
Subjects:	Analytical Chemistry
Divisions:	Departments > Department of Biochemistry and medical chemistry
Depositing User:	Анастасия Жигар
Date Deposited:	20 Apr 2026 11:35
Last Modified:	20 Apr 2026 11:35
URI:	http://repo.dma.dp.ua/id/eprint/9852

Actions (login required)

View Item