In the present study, a new biosensor for 5-Fluorouracil was described using modified goldelectrode and Fast Fourier transform square wave voltammetry (FFT SWV). Calf thymus DNAimmobilization was on a gold electrode decorated with polyaniline and gold nanoparticles. Theelectrochemical characteristics of the electrodes were investigated by cyclic voltammetry, andelectroch...

In this study a sensitive electrochemical sensor for the detection of E.coli has been developed using silver nanoparticle (Ag) embedded poly(9,9-dioctylfluorene-ran-phenylene) (CFP) nanocomposite as a conductive platform and DNA hybridization technique. The new polymer was synthesized from 9,9-dioctylfluorene and 1,3-dichlorobenzene and biphenyl through Friedel Crafts alkylation reacti...

A fiber optic biosensor based on DNA aptamers used as receptors was developed for the measurement of throm bin concentration. Anti thrombin DNA aptamers were immobilized on silica microspheres, placed inside microwells on the distal tip on an imaging optical fiber, coupled to a modified epifluorescence microscope through its proximal tip. Thrombin concentration is determined by a competitive bi...

objective(s): this paper describes a selective and sensitive biosensor based on the dissolution and aggregation of aptamer wrapped single-walled carbon nanotubes. we report on the direct detection of aptamer–cocaine interactions, namely between a dna aptamer and cocaine molecules based on near-infrared absorption at λ807. materials and methods: first a dna aptamer recognizing cocaine was non-co...

F0F1-ATPase within chromatophore was constructed as a molecular motor biosensor through ε-subunit antibody-biotin-streptavidin-biotin-AC5-Sulfo-Osu system. Based on probe-DNA specific binding, DNA of several foodborne pathogens Listeria monocytogenes, Salmonella typhimurium, Vibrio parahaemolyticus and Vibrio cholerae was specifically captured by F0F1-ATPase molecular motor biosensors. Loads of...

Quartz Crystal Microbalance (QCM) biosensor technology was used to study the interaction of the DNA-binding domain (DBD) of the transcription factor RXRα with immobilized specific (DR1) and unspecific (DR1neg) DNA oligoduplexes. We identify the QCM sensor frequency at the susceptance minimum (fBmin) as a better measuring parameter, and we show that fBmin is proportional to the mass adsorbed at ...

The redox mechanism of two trisubstituted triazole-linked phenyl derivatives (CL41 and CL42) and a disubstituted triazole-linked phenyl derivative (CL2r50) were studied using cyclic, differential pulse and square wave voltammetry at a glassy carbon electrode. The CL41, CL42 and CL2r50 oxidation is a complex, pH-dependent irreversible process involving the formation of electroactive products tha...

Gene expression, catalysed by RNA polymerases (RNAP), is one of the most fundamental processes in living cells. The majority of methods to quantify mRNA are based upon purification of the nucleic acid which leads to experimental inaccuracies and loss of product, or use of high cost dyes and sensitive spectrophotometers. Here, we describe the use of a fluorescent biosensor based upon the single ...

Circulating tumor DNA (ctDNA), which includes DNA mutations, epigenetic alterations and other forms of tumor-specific abnormalities, is a promising "real-time" biomarker for noninvasive cancer assessment. Tumor DNA is of great value in the process of cancer treatment, including diagnostic and prognostic information before, during treatment and at progression. Here we introduce a peptide nucleic...