Sol–gel derived carbon ceramic composite electrode containing a ruthenium complex for amperometric detection of insulin at physiological pH

Surface renewable sol–gel composite electrode derived from 3-aminopropyl trimethoxy silane with covalently immobilized thionin

“…This problem can be solved by covalent linking of the mediator with sol-gel precursors. Bifunctional sol-gel precursors such as (3-aminopropyl) trimethoxy silane and (3-mercaptopropyl) trimethoxy silane offers the additional advantage of surface modification due to the presence of free amino and thiol groups that could be used as the binding site for covalent attachment Salimi et al, 2003). These functional sol-gel precursors facilitate the construction of sensing materials with possible control over the selective modification, orientation and distribution of catalytic sites (Jin and Brennan, 2002;Shen et al, 2005).…”

Glucose biosensor prepared by glucose oxidase encapsulated sol-gel and carbon-nanotube-modified basal plane pyrolytic graphite electrode

“…Although the two methods have been used successfully for immobilization of glucose oxidase and electron transfer mediators, in the bulk modification method a substantial amount of enzyme and carbon nanotube are needed for the electrode fabrication. In continuation of our studies, to prepare modified electrodes based on the sol-gel technique [31][32][33][34][35] and carbon nanotubes [36] and to overcome these disadvantages, in the present study a two-step modification was used for fabrication of biosensors with carbon nanotubes and glucose oxidase. In the first step the basal plane pyrolytic graphite (bppg) electrode is modified by abrasives on carbon nanotube particles; in the second step the modified electrode is covered by a thin film of sol-gel composite containing glucose oxidase.…”

Cobalt oxide nanostructure-modified glassy carbon electrode as a highly sensitive flow injection amperometric sensor for the picomolar detection of insulin

“…Low sensitivity, stability and reproducibility, slow kinetics, surface fouling, and high overpotential at which the insulin oxidation process occurred are the limitations of unmodified electrodes. Various electron transfer mediators have been used for the electrooxidation and determination of insulin [41][42][43][44][45][46][47][48][49][50][51][52][53][54][55][56]. Although the modified electrodes have been successfully employed for monitoring insulin, they usually have many disadvantages such as reduced stability and activity under a physiological condition, high detection limit, poor longterm stability, and complicated multi-step preparation methods.…”