A potentiometric enzyme biosensor for the direct measurement of organophosphate pesticides was developed. The basic element of this enzyme biosensor was a pH electrode modified with an immobilized organophosphorus hydrolase layer formed by cross-linking OPH with bovine serum albumin and glutaraldehyde. Organophosphorus hydrolase catalyzes the hydrolysis of organophosporus pesticides to release ...

We report a biosensor based on organophosphorus hydrolase (OPH) multilayer modified microcantilever (MCL) for detection of organophosphorus compounds (OPs). The assay is based on substrate-dependent bending of the OPH functionalized MCLs. The cantilever bending amplitude at equilibrium was a function of the concentration of paraoxon with the dynamic range extending from 10(-7) to 10(-3)M. The l...

An optical microbial biosensor was described for the detection of methyl parathion pesticide. Whole cells of Flavobacterium sp. were immobilized by trapping in glass fiber filter and were used as biocomponent along with optic fiber system. Flavobacterium sp. has the organophosphorus hydrolase enzyme, which hydrolyzes the methyl parathion into detectable product p-nitrophenol. The immobilized mi...

Enzymes that are capable of degrading neurotoxic organophosphorus compounds are of increasing interest because of the lack of efficient and clean methods for their removal. Recently, a novel organophosphorus hydrolase belonging to the metallo-β-lactamase superfamily was identified and isolated from the mesophilic bacterium Pseudomonas pseudoalcaligenes. This enzyme, named OPHC2, is endowed with...

Enzyme sensor for organophosphorus insecticides organophosphorus hydrolase in a polymer membrane on a pH sensor is used to catalyse the hydrolysis of compounds with phoshate ester functionality. The detected [H+] change is proportional to the concentration of the phosphate ester insecticide. This is a good example of the use of an enzyme to give selectivity to a specific class of compounds. Unf...

A new biometallization route for detecting low levels of organophosphorus nerve agents based on organophosphorus-hydrolase (OPH)-stimulated formation of cupric-ferrocyanide (CuFeCN) nanoparticles is described. The growth and accumulation of these nanoparticles onto the surface of carbon paste electrodes, coupled with their favorable redox activity, allow the amplified electrochemical detection ...

Organophosphorus (OP) pesticides can be rapidly detected by integrating organophosphorus hydrolase with an optical leaky waveguide biosensor. This enzyme catalyses the hydrolysis of a wide range of organophosphorus compounds causing an increase in the pH. Thus, the direct detection of OP is possible by monitoring of the pH changes associated with the enzyme's activity. This article describes th...

A simple approach to enhancing the activity and stability of organophosphorus hydrolase (OPH) is developed based on interactions between the hydrophobic poly(propylene oxide) (PPO) block of amphiphilic Pluronics and the enzyme. This strategy provides an efficient route to new formulations for decontaminating organophosphate neurotoxins.

A novel capacitive field-effect sensor for the direct determination of organophosphorus pesticides by the enzyme organophosphorus hydrolase (OPH) is presented. The enzyme OPH hydrolyses organophosphorus compounds catalytically, thus releasing Hþ ions. By means of a silicon-based field-effect sensor, which consists of a layer sequence of Al/p-Si/SiO2 with alternative pH-sensitive materials (Ta2O...