High-performance amperometric biosensor for flow injection analysis consisting of a replaceable lactate oxidase-based mini-reactor and a silver amalgam screen-printed electrode

0568897 - ÚFCH JH 2024 RIV GB eng J - Journal Article
Tvorynska, Sofiia - Barek, J. - Josypčuk, Bohdan
High-performance amperometric biosensor for flow injection analysis consisting of a replaceable lactate oxidase-based mini-reactor and a silver amalgam screen-printed electrode.
Electrochimica acta. Roč. 445, MAR 2023 (2023), č. článku 142033. ISSN 0013-4686. E-ISSN 1873-3859
R&D Projects: GA ČR(CZ) GA20-07350S
Institutional support: RVO:61388955
Keywords : Amperometric biosensor * Flow injection analysis * enzymatic mini-reactor
OECD category: Electrochemistry (dry cells, batteries, fuel cells, corrosion metals, electrolysis)
Impact factor: 6.6, year: 2022
Method of publishing: Limited access

L-lactic acid (LA) is an essential compound in the winemaking process. Furthermore, it is considered a significant biomarker for the diagnosis of a wide range of diseases, including cancer. Therefore, a cost-effective and reliable biosensing system for FIA is developed here for rapid and selective determination of LA. The biosensor architecture includes an easily replaceable lactate oxidase (LOx)-based mini-reactor connected in front of a silver amalgam screen-printed electrode acting as a transducer. The mini-reactor represents a tube filled with mesoporous silica powder (SBA−15) coated with covalently immobilized LOx. The principle of LA determination is based on the amperometric monitoring of oxygen consumption by its four-electron reduction at −900 mV vs. Ag pseudo-reference electrode, which avoids the interferences from commonly interfering compounds. The application of a strategy of a spatially separated biorecognition and detection part allowed for the immobilization of a notably large amount of enzyme (one mini-reactor contains c.a. 270 μg of the LOx), which, in turn, ensured excellent operational (93.8% of the initial signal after 350 measurements) and storage (96.9% of the initial biosensor response after 7 months) stability. The newly developed high-performance biosensor was successfully tested for the quantification of LA in saliva, wine, and dairy products.
Permanent Link: https://hdl.handle.net/11104/0340175