An electrochemical biosensor based on sulfonated graphene/polyaniline nanocomposite was developed for urea analysis. Oxidative polymerization of aniline in the presence of sulfonated graphene oxide was carried out by electrochemical methods in an aqueous environment. The structural properties of the nanocomposite were characterized by Fourier-transform infrared, Raman spectroscopy, X-ray photoe...

In food sector, there is a huge demand for rapid, reliable, user & eco-friendly biosensors to analyse the quality and safety of food products. Biosensor based methodology depends upon the recognition of a specific antigens or receptors by corresponding antibodies, aptamers or high-affinity ligands. The first scientifically commercialised sensors were the electrochemical sensors used for the ana...

DNA methylation is one of important epigenetics events, and responsible to transcription, genomic imprinting and cellular differentiation. Aberrant DNA methylation is always contacted with various diseases. Methyl binding domain (MBD) proteins can specifically bind to the methylated CpG dinucleotides. Conventional assay for DNA methylation normally need bisulfide treatment, methylated nucleotid...

In this work, a novel strategy to fabricate a highly sensitive and selective biosensor for the detection of Ag(+) is proposed. Two DNA probes are designed and modified on a gold electrode surface by gold-sulfur chemistry and hybridization. In the presence of Ag(+), cytosine-Ag(+)-cytosine composite forms and facilitates the ligation event on the electrode surface, which can block the release of...

In food sector, there is a huge demand for rapid, reliable, user & eco-friendly biosensors to analyse the quality and safety of food products. Biosensor based methodology depends upon the recognition of a specific antigens or receptors by corresponding antibodies, aptamers or high-affinity ligands. The first scientifically commercialised sensors were the electrochemical sensors used for the ana...

electrochemical aptamer-based sensors attract a lot of interest as useful methods because of their low cost, accuracy, sensitivity, and simplicity. an electro-active redox molecule comprises the main part of the electrochemical-based sensors. ferrocene is one of the most popular redox molecule used in biosensor fabrication. but, instability of ferrocenium ion in strong nucleophilic reagents and...

The conventional methods used for specific sequences detection in nucleic acids based on DNA sequence polymerization (PCR) or DNA hybridization (FISH), present certain drawbacks such as the requirement of expensive equipment, time-consuming, laborious and in some case a low sensitivity. Therefore, biosensors are the most attractive alternative providing simple, reliable, fast and selective dete...

Hydrogen peroxide (H2O2) plays a pivotal role in various industrial applications [1]. It is an essential mediator in pharmaceutical, clinical, and environmental research. In addition, it is a byproduct of highly selective oxidases and an important contaminant in several industrial products and wastes [2]. Therefore, a reliable and economical method for the determination of H2O2 is of great sign...

The determination of cholesterol is increasingly important for the fact that high serum cholesterol level was related with many diseases. In this work, a new cholesterol biosensor was developed based on the gold-graphene nanocomposite material prepared by one-step electrodeposition. The nanomaterial formed on a glassy carbon electrode was proved by scanning electron microscope and the electroch...

The performance of glassy carbon (GCE) and graphite pencil electrodes (PGE) modified with multiwalled carbon nanotubes (CNTs) are compared, based on the direct electrochemical detection of nucleic acids. This is accomplished by monitoring the differential pulse voltammetry changes of the guanine signal. CNT-modified PGE compares favorably to that of the commonly used CNT-modified GCE owing to t...