Biosensors have been developed for the detection of pesticides using integrated enzymes, antibodies, cell and DNA-based biosensors. Enzymatic determination of pesticides is most often based on inhibition of the activity of selected enzymes such as cholinesterase, acid phosphatase, ascorbate oxidase, acetolactate synthase and aldehyde dehydrogenase. Enzymatic Biosensors were developed using vari...

Cholinesterase sensors based on screen-printed electrodes modified with polyaniline, 7,7',8,8'-tetracyanoquinodimethane (TCNQ), and Prussian blue have been developed and tested for detection of anticholinesterase pesticides in aqueous solution and in spiked grape juice. The influence of enzyme source and detection mode on biosensor performance was explored. It was shown that modification of the...

Methods Our study included six patients with acquired infection from central catheter; the microbial pathogens were Streptococcus viridans (n = 3) and Staphyloccocus aureus (n = 3). The diagnosis of IE was based on positive blood culture (2 positive cultures of blood samples drawn > 12 hours), evidence of endocardial involvement (positive ECHO), measuring raised erythrocyte sedimentation rate a...

organophosphate chronic toxicity has been evaluated in this study. biological screening for organophosphate insecticide-exposed workers is mostly recommended for mixers, loaders, formulators and spraymen. we have studied 17 occupationally exposed persons to pesticides. using ellman's colorimetric method, their plasma cholinesterase activities have been measured. results show that the appea...

For 6 months after renal transplant serum cholinesterase concentrations were measured in 10 patients. The value decreased in the first 15 days after operation, but was normal thereafter. Liver function tests were normal throughout the study; the cholinesterase changes were independent of immunosuppressive therapy.

Arsenic is an environmental toxicant, and one of the major mechanisms by which it exerts its toxic effect is through an impairment of cellular respiration by inhibition of various mitochondrial enzymes, and the uncoupling of oxidative phosphorylation. Most toxicity of arsenic results from its ability to interact with sulfhydryl groups of proteins and enzymes, and to substitute phosphorus in a v...

We investigated three methods for determination of cholinesterase (ChE) in human blood sera, using reference sera, sera of known ChE content, and serum variously diluted with deactivated sera. The methods were the Du Pont aca analyzer, the Pfizer "ChE-tel" method, and the Michel method with and without direct reagent-blank correction. With respect to precision and reproducibility the methods ra...