The need for assay methods of sufficient sensitivity to determine the low concentrations of hormones present in body fluids led to the original development of immunoassays and analogous “binding” (or “ligand”) assays in the late 1950s and early 1960s. These methods depend on the use of a binding agent (also commonly referred to by other terms such as “receptor,” “binding reagent,” and “analyte-...

Hepatitis B core Antigen (or HBcAg) is the major component of the core particles of Hepatitis B virus (or HBV). Particles have a size of 27 nm and contain a circular double-stranded DNA molecule, a specific DNA-polymerase and HBcAg. HBcAg is composed of a single polypeptide of about 17 kD that is released upon disaggregation of the core particles; the antigen contains at least one immunological...

This paper describes an electrochemical enzyme-linked immunosorbent assay (ELISA) on paper-based microfluidic devices. This paper-based immunoassay method has several advantages over conventional ELISA, such as short assay time, low cost, and high sensitivity. The limit of detection (LOD) of rabbit IgG used as a model system is ~ 3.9 fM; this value is lower than the LOD of paper-based colorimet...

HBsAg is one of the earliest markers that appear in the blood following infection with Hepatitis B virus (HBV). This infection of the liver is transmitted by homosexual or heterosexual activity, blood borne exposure, mother infant, close personal contact and by intake of contaminated water and food products. In the HBV infected people, the virus persists for the rest of their lives and can be p...

ABSTRACT: Bovine viral diarrhea virus (BVDV) is a highly infectious pathogen that affects bovines worldwide leading to great economic impact. Although Brazil has the largest commercial cattle population throughout world and an increasing buffalo breeding industry, country no control or eradication program for BVDV. In this perspective, aim of study was evaluate occurrence BVDV in buffaloes from...