Several redox enzymes were examined for enzymatic/electrochemical-recycling systems in order to measure p-aminophenol (PAP) with high sensitivity. Glucose oxidase (GOD) and diaphorase (DI) worked well as catalysts for recycling electrode systems: these enzymes effectively reduced p-iminoquinone (PIQ), the electrochemically-oxidized form of PAP, and caused an enhancement in the electrochemical s...

Nanostructures Chengzhou Zhu,†,§ Guohai Yang,†,§ He Li,†,§ Dan Du,† and Yuehe Lin*,†,‡ †School of Mechanical and Materials Engineering, Washington State University, Pullman, Washington 99164, United States ‡Pacific Northwest National Laboratory, Richland, Washington 99352, United States ■ CONTENTS Nonenzymatic Sensors 231 Glucose 231 Hydrogen Peroxide 231 Cation 232 Anion 232 Other Species 232 ...

A simple and accurate label-free amperometric immunosensor for α-fetoprotein (AFP) detection is developed based on gold nanorods (GNRs) with different aspect ratio and compared with gold particles (GNPs). The positively charged GNRs and GNPs due to the surface immobilized cetyltrimethyl ammonium bromide (CTAB) can adsorb the negatively charged AFP antibody (Ab) directly. The presence of the GNR...

Immunoassays have been widely used as the standard technology for quantitative detection of analyte concentrations in the fields of medicine, environmental science, and food science. Immunoassays such as enzyme-linked immunosorbent assays (ELISA), fluorescence immunoassays (FIA), electrochemical immunoassay (EIA), immunoagglutination assays (IAA) and radioimmunoassays (RIA) are the most commonl...

Using phenytoin as a model analyte, we demonstrate an electrochemical enzyme immunoassay based on flow-injection analysis and incorporating 2,6-dichloroindophenol (DCIP) as a redox coupling agent. DCIP reacts with NADH to form NAD+ and DCIPH2, the reduced form of the coupling agent. The production of DCIPH2 is monitored at +250 mV vs Ag/AgCl. This low applied potential improves selectivity in t...

results analyzing of collected data resulted in the wrapping up the hepatitis virus detection methods in separate sections including 1) immunological methods such as enzyme immunoassay (eia), radio-immunoassay (ria) immuno-chromatographic assay (ica), and immuno-chemiluminescence 2) molecular approaches including non-amplification and amplification based methods, and finally 3) advanced biosens...

Carbohydrate antigen 19-9 (CA19-9) is an important biomarker for the early diagnosis and clinical monitoring of pancreatic cancer. Reliable, simple, and accurate methods for the detection of CA19-9 are still urgently needed. In this study, polythionine-Au composites (AuNPs@ PThi) were designed and prepared through one-pot reaction using HAuCl4 as the co-oxidant and raw material in thionine solu...

Superoxide Dismutase-Based Third-Generation Biosensor for Superoxide Anion Electrochemical Immunoassay Moving into the Fast Lane Characterization and Reactions of Previously Elusive 17Electron Cations: Electrochemical Oxidations of (C H )Cr(CO) and (C H )Co(CO) in the Presence of [B(C F ) ] Although chemical redox reagents can be highly selective, many produce toxic b y p r o d u c t s . I n c ...