A disposable biosensor based on acetylcholinesterase-functionalized acid purified multi-wall carbon nanotubes (CNTs) modified thick film strip electrode for organophosphorus (OP) insecticides was developed. The degree of inhibition of the enzyme acteylcholinesterase (AChE) by OP compounds was determined by measuring the electrooxidation current of the thiocholine generated by the AChE catalyzed...

The cholinesterase activity of the sera of 25 subjects diagnosed as homozygotes for the silent cholinesterase gene was studied by a sensitive enzymatic method employing several thiocholine esters and various inhibitors, and by disc electrophoretic, immunochemical, and chromatographic methods.(a) With one exception, the sera fell into two classes by all criteria. One class (type I, 16 cases) had...

Carbon nanotubes are regarded as promising building blocks for the construction of novel biosensors due to their unique properties like fast electron transfer, high electrocatalytic effect and good biocompatibility. In the present study, the effect of different chemical oxidation’s methods of multi-walled carbon nanotubes (MWCNTs) on the electrochemical behavior of modified graphite electrodes ...

In this paper, we integrated acetylcholinesterase (AChE) biosensor and detection system to fabricate pesticides residues portable detection instrument for an on-site use. The AChE biosensor was based on the inhibition of enzyme activity that was monitored by the change of oxidation current of the thiocholine using ordinary three electrodes and an own designed potentiostat. The current signal ge...

Since the appearance of the first amperometric biosensors based on the coupling of oxidase enzymes and relying on the final detection of H2O2, it was clear that one of the major problems related to this kind of configuration was due to the high overpotential needed for H2O2 oxidation (ca. 0.7V vs. Ag/AgCl). At this potential in fact, many electroactive substances (i.e. ascorbic acid, uric acid ...

In this report, we have developed a plasmonic ELISA strategy for the detection of syphilis. Plasmonic ELISA is an enzyme-linked immunoassay combined with enzyme-mediated surface plasmon resonance (SPR) of gold nanoparticles (AuNPs). Immune response of the Treponema pallidum (T. pallidum) antibodies triggers the acetylcholinesterase-catalyzed hydrolysis of acetylthiocholine to produce abundant t...

A renewable, disposable, low cost, and sensitive sensor for the detection of organophosphorus pesticides was constructed by immobilizing the acetylcholinesterase enzyme (AChE), via glutaraldehyde, on magnetic iron nanoparticles (Fe₃O₄) previously synthesized and functionalized with chitosan (CS). The sensor was denoted AChE/CS/Fe₃O₄. The magnetic nanoparticles were characterized by Fourier tran...

Using the thiocholine method of Koelle and Friedenwald and histological techniques the pterygopalatine ganglion in Egyptian spiny mouse (Acomys cahirinus, Desmarest) was studied. The ganglion was found to be a single irregular cluster of neurocytes, situated on the medial surface of the maxillary nerve. The ganglion is composed of oval, elliptical and sometimes fusiform ganglionic neurones in c...