Minimizing overpotential and generating high faradaic currents are critical issues for fast-scan voltammetry of beta-nicotinamide adenine dinucleotide (NADH) for the sensitivity of enzyme-modified electrodes based on dehydrogenases. Although NADH voltammetry exhibits high overpotential and poor voltammetric peak shape at solid electrode surfaces, modification of the electrode surface can improv...

Непрерывный мониторинг глюкозы (НМГ) считается наиболее совершенной системой малоинвазивного контроля уровня сахара в крови. Рабочий электрод датчика для НМГ должен обладать такими свойствами, как гибкость обеспечения безопасности внедрения под кожу, стабильность аналитического сигнала, устойчивость к воздействию температуры, pH среды, влажности и механической нагрузки (трение об одежду при нош...

We report a label-free and ultrasensitive aptasensor based on a fractal gold modified (FracAu) electrode for thrombin detection with a femtomolar detection limit. The FracAu electrode was prepared by electrodeposition of hydrogen tetrachloroaurate (HAuCl(4)) onto a bare indium tin oxide (ITO) electrode surface. After this process the electrode was characterized by SEM. A thiol-modified aptamer ...

We report the non-covalent functionalization of a multi-walled carbon nanotube (MWCNT) electrode with a biomimetic model of the horseradish peroxidase (HRP) active site. By modifying the MWCNT electrode surface with imidazole-modified polypyrrole, a new biomimetic complex of HRP was synthesized on the MWCNT sidewalls via the coordination of imidazole (Im) to the metal centre of iron protoporphy...

The research has developed an enzyme biosensor for the detection organophosphate pesticide residues. The biosensor consists of a pair of screen-printed carbon electrode (SPCEs). One of electrodes contains immobilized organophosphate hydrolase (OPH) on a chitosan membrane by cross-linking it with glutaraldehyde. The area of the electrodes was optimized to 3, 5, and 7 mm(2). The OPH was isolated ...

We report an approach for spatially selective assembly of an enzyme onto selected patterns of microfabricated chips. Our approach is based on electrodeposition of the aminopolysaccharide chitosan onto selected electrode patterns and covalent conjugation of a target enzyme to chitosan upon biochemical activation of a genetically fused "pro-tag." We report assembly of S-adenosylhomocysteine nucle...

The described glucose biosensor is based on a screen-printed carbon electrode (SPCE) modified by rhodium dioxide, which functions as a mediator. The electrode is further modified by the enzyme glucose dehydrogenase, which is immobilized on the electrode's surface through electropolymerization with m-phenylenediamine. The enzyme biosensor was optimized and tested in model glucose samples. The bi...

A new continuous-flow automated enzymatic method suitable for the direct determination of creatinine in physiological samples is described. The proposed system utilizes an on-line gas predialysis unit in conjunction with a flow-through enzyme reactor coil and a potentiometric ammonia detector. The enzyme reactor contains immobilized creatinine iminohydrolase (EC 3.5.4.21) which converts creatin...