Effect of Protection Polymer Coatings on the Performance of an Amperometric Galactose Biosensor in Human Plasma.

Galactose monitoring in individuals allows the prevention of harsh health conditions related to hereditary metabolic diseases like galactosemia. Current methods of galactose detection need development to obtain cheaper, more reliable, and more specific sensors. Enzyme-containing amperometric sensors based on galactose oxidase activity are a promising approach, which can be enhanced by means of their inclusion in a redox polymer coating. This strategy simultaneously allows the immobilization of the biocatalyst to the electroactive surface and hosts the electron shuttling units. An additional deposition of capping polymers prevents external interferences like ascorbic or uric acid as well as biofouling when measuring in physiological fuels. This work studies the protection effect of poly(2-methacryloyloxyethyl phosphorylcholine-co-glycidyl methacrylate (MPC) and polyvinylimidazole-polysulfostyrene (P(VI-SS)) when incorporated in the biosensor design for the detection of galactose in human plasma.

Designed affinity ligands to capture human serum albumin.

Human serum albumin (HSA) in an important therapeutic agent and disease biomarker, with an increasing market demand. By proteins and drugs that bind to HSA as inspiration, a combinatorial library of 64 triazine-based ligands was rationally designed and screened for HSA binding at physiological conditions. Two triazine-based lead ligands (A3A2 and A6A5), presenting more than 50% HSA bound and high enrichment factors, were selected for further studies. Binding and elution conditions for HSA purification from human plasma were optimized for both ligands. The A6A5 adsorbent yielded a purified HSA sample with 98% purity at 100% recovery yield under mild binding and elution conditions.