National Repository of Grey Literature 2 records found  Search took 0.00 seconds. 
Construction and Application of Flow Amperometric Biosensor Based on Enzymatic Reactor for Determination of Choline
Tvorynska, Sofiia ; Barek, J. ; Josypčuk, Bohdan
In this contribution, a novel fast, simple and stable biosensor with the enzymatic reactor based on choline oxidase (ChOx) was developed and applied for the determination of choline using flow injection analysis with amperometric detection. The preparation of the reactor is based on the covalent immobilization of ChOx with glutaraldehyde to mesoporous silica powder (SBA-15) previously covered by NH2-groups. The experimental parameters affecting the sensitivity and stability of the biosensor were optimized. The proposed biosensor with the newly developed ChOx-based reactor possesses good repeatability, reproducibility, long-term stability, and reusability. It was successfully applied for the determination of choline in commercial pharmaceuticals.
Silver Solid Amalgam Electrodes as Perspective Tools for Sensitive Voltammetric Determinations of Food Azo Dyes Amaranth and Allura Red AC
Tvorynska, S. ; Barek, J. ; Josypčuk, Bohdan
In this paper, for the first time, the electrochemical behaviours of the food azo dyes Amaranth (E 123) and Allura Red AC (E 129) were investigated on two modifications of silver solid amalgam electrode, namely mercury meniscus modified, polished and compared with hanging mercury drop electrode using differential pulse voltammetry and direct current voltammetry. The effect of adsorption and the reduction mechanism on tested electrodes were described in detail. Measurements with amalgam electrodes showed good reproducibility, stability and high sensitivity. As a result, they were successfully applied for the determination of investigated azo dyes in different commercial drink samples.

See also: similar author names
1 Tvorynska, Sofiia
Interested in being notified about new results for this query?
Subscribe to the RSS feed.