An interference-free amperometric biosensor for the quantitative xanthine analysis is described. Xanthine was monitored through the electrochemical reduction of hydrogen peroxide (produced upon its enzyme-catalyzed oxidation) at a constant applied potential of -50 mV (vs. Ag/AgCl). The biosensor was designed on the basis of a graphite electrode modified with microquantities of platinum and pall...

The research is focused on investigation of impact of parameters of bi-layer monoenzyme amperometric biosensor to its characteristics: the sensitivity and the enzyme volume. The bi-objective optimization problem of determination of the optimal thicknesses of the layers and maximal enzymatic rate of the biosensor with respect to maximization of the sensitivity and simultaneously minimization of ...

The solution properties of some cationic polyelectrolytes with ammonium quaternary centers either attached to an acrylic macromolecular chain (polycation PDMAEMQ type) or in the backbone (polycation PCA type) have been measured in order to identify how charge density, polyelectrolyte concentration, solvent polarity as well as temperature influence their behavior in solution by viscometric, cond...

Laccase enzyme, a commonly used enzyme for the construction of biosensors for phenolic compounds was used for the first time to develop a new biosensor for the determination of the azo-dye tartrazine. The electrochemical biosensor was based on the immobilization of laccase on functionalized methacrylate-acrylate microspheres. The biosensor membrane is a composite of the laccase conjugated micro...

Accurate and timely detection of bacterial pathogens will improve the clinical management of infections. Herein, we demonstrate an electrochemical biosensor that directly detects bacteria in human blood samples, resulting in the rapid diagnosis of a bloodstream infection. The multiplex biosensor detects the species-specific sequences of the 16S ribosomal RNA of bacteria for pathogen identificat...

Molybdenum electrode based flexible biosensor on porous polyamide substrates has been fabricated and tested for its functionality as a protein affinity based biosensor. The biosensor performance was evaluated using a key cardiac biomarker; cardiac Troponin-I (cTnI). Molybdenum is a transition metal and demonstrates electrochemical behavior upon interaction with an electrolyte. We have leveraged...

PURPOSE A novel system, based on biosensor DNA tethered to a nanoparticle, was developed for the treatment of retinopathy of prematurity. METHODS The construction of a five-layered nanoparticle was visualized with gel electrophoresis. Transcriptionally active PCR products (TAP) containing the biosensor sequence, were bioconjugated to the surface of magnetic nanoparticles yielding biosensor te...

BACKGROUND Soluble CD147 (sCD147) is the shed form of membrane-bound CD147, which is involved in the regulation of cellular functions. The presence of sCD147 in body fluids is associated with several diseases. OBJECTIVE In this study, we aimed to establish antibody (Ab) biosensors for the simultaneous differential detection of the general and truncated forms of sCD147. METHOD By combining b...

A microbial whole-cell biosensor was developed, and its potential to measure water-dissolved concentrations of middle-chain-length alkanes and some related compounds by bioluminescence was characterized. The biosensor strain Escherichia coli DH5 alpha(pGEc74, pJAMA7) carried the regulatory gene alkS from Pseudomonas oleovorans and a transcriptional fusion of PalkB from the same strain with the ...

Aspartate aminotransaminase (AST) is a hepatocelluar enzyme released into the bloodstream when hepatic cells are damaged, resulting in elevated blood levels of AST. A single use, disposable biosensor prototype, composed of catalytic iridium nano-particles dispersed on carbon paste, was developed to detect enzymatically-produced H2O2 in AST-mediated reactions. This biosensor is capable of measur...