Electrochemical Biosensor for Sensitive Detection of Hepatitis B in Human Plasma.

In this work, we report the construction of a novel electrochemical device for molecular diagnosis of hepatitis B virus in the blood plasma of infected patients, using graphite electrodes functionalized with poly(4-aminophenol) and sensitized with a specific DNA probe. The recognition of genomic DNA was evaluated by electrochemical techniques (DPV and EIS) and scanning electron microscopy. The genosensor was efficient in detecting genomic DNA with a linear range from 1.

Innovative approaches to improve serodiagnosis of Strongyloides stercoralis infection.

Strongyloidiasis is a helminthiasis of neglected condition that has no gold standard parasitological diagnosis due to the intermittent release of larvae in feces. This study aimed to use an scFv (single chain variable fragment) obtained by Phage Display, previously validated to detect immune complexes in serum samples from individuals infected with Strongyloides stercoralis by enzyme-linked immunosorbent assay (ELISA). Now the ability of scFv to detect the immune complexes was verified by immunofluorescence, flow cytometry using magnetic beads and surface plasmon resonance (SPR).

Serological Electrodetection of Rheumatoid Arthritis Using Mimetic Peptide.

Background: Rheumatoid arthritis is the most common inflammatory autoimmune disease in the world. Recently new targets for its detection were developed as alternatives to classic biomarkers, including the M-12 peptide, that mimics carbonic anhydrase III. Thus, the application of this peptide for the development of new detection devices is attractive.

Molecular modeling study on the possible polymers formed during the electropolymerization of 3-hydroxyphenylacetic acid.

The compound 3-hydroxyphenylacetic acid (3-HPA) has been used as a monomer in the synthesis of polymeric films by electropolymerization; these films serve as supports for the immobilization of biomolecules in electrochemical biosensors. To assist in the elucidation of the mechanism of 3-HPA electropolymerization, a systematic quantum mechanical study was conducted. In addition to the monomer, all possible intermediates and the probable oligomers formed during the electropolymerization were investigated using a density functional theory (DFT) method combined with a previous conformational analysis performed with the aid of the RM1 semi-empirical method or a Monte Carlo conformational analysis with the force field OPLS-2005.

Recent advances in nano-based electrochemical biosensors: application in diagnosis and monitoring of diseases.

Based on biological molecules combined with nanostructured components, the news generations of electrochemical biosensors can employ different transducers (potentiometric, amperometric and impedimetric) converting the chemical information into a measurable amperometric signal. Following this contemporary theme, our main focus in this review is to discuss different methodologies for application in biosensing, whose signal transduction is based on electrochemical principles. We apply a discussion on recent trends involving different nanostructured materials, but without daring to contemplate all nanomaterials incessantly cited in literature, which leads us to believe that this moment is an unprecedented revolution in the preparation of electrochemical biodevices.