Matrix metalloproteinases (MMPs) regulate composition of the extracellular matrix and play a critical role in cancer, fibrosis, and wound healing. This article describes a novel peptide-based electrochemical biosensor for detecting activity of cell-secreted protease MMP9. In this sensing strategy, a peptide specific to MMP9 was modified with a redox label (methylene blue (MB)) and immobilized o...

Pharmaceutical drugs play an important role in human life since they caused a revolution in human health. Notably, their administration to a living organism helps body to stay healthy. Commonly, they are employed to diagnose, prevent, or treat and cure a disease via a biological effect on a human body. Administration of impurity-free and adequate amounts of pharmaceut...

The entrapment method was used to prepare electrochemical biosensors. Using controlled potential method, copolymers were synthesized between aniline y sulfonated-anilines in aqueous media at pH 4.9 on Platinum disc. The copolymers were characterized by elemental analysis and spectroscopy. Glucose-oxidase was entrapped in the electropolymerization process, at pH 4.9 in aqueous media. The copolym...

We have used novel microporous biphenylene-pillared layered silicates as receptors in a quartz crystal microbalance (QCM) for sensing toluene vapors. The silicate was successfully coated on a QCM electrode modified with 2-aminoethanethiol. The resultant electrode showed quantitative frequency responses due to enhanced adhesion between the silicate and the electrode. The silicate-coated electrod...

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...

The formation of self-assembled monolayers (SAM) of 5,5%-dithiobis (2-nitrobenzoic acid), DNBA on gold has enabled further derivatization of the electrode surface with functional moieties anchored to the surface bound molecules. A SAM of DNBA was formed on the Au surface. Nickel ions tethered to the SAM-covered Au surface, were subsequently derivatized electrochemically to yield nickel hydroxid...

Multi-walled carbon nanotubes (MWCNT) modified DNA based biosensors were prepared by immobilizing dsDNA over MWCNT coated graphite electrode. The film forming abilities of MWCNT coated graphite electrodes were studied using Electrochemical Impedance Spectroscopy (EIS) and Cyclic Voltammetry (CV) by placing the electrodes in electrolyte containing redox couple. Differential Pulse Voltammetry (DP...

New donor–acceptor polymers containing disilanobithiophene (DSBT) as the donor and pyridine or pyrazine as the acceptor with or without a thiophene spacer were prepared. The polymers showed UV-vis absorption maxima at lmax 1⁄4 488–526 nm, which were red-shifted relative to those of model monomers dithienylpyridine and dithienylpyrazine (lmax 1⁄4 352–375 nm), indicating the efficient conjugation...

The electrochemical behavior of cytochrome c (cyt-c ) adsorbed to gold electrodes through mercaptoalkanoic acid/ mercaptoalcohol monolayers was investigated in the 1-butyl-3-methylimidazolium salts of bis(trifluoromethylsulfonyl)imide and hexafluorophosphate. Cyt-c does not retain its Fe(III)/Fe(II) redox activity in dry ionic liquids (ILs); however, the redox signal of the modified electrodes ...

This work reports on the electrocatalytic oxidation of hydroxide using different central metal ion phthalocyanines and porphyrins immobilized on gold electrodes. The apparent electrocatalytic activity of cobalt phthalocyanine or porphyrin modified electrodes was found to be the greatest among the present series of metal ion macrocycles investigated. Copper and unmetallated phthalocyanine or por...