Affinity measurements of biological molecules by a quartz crystal microbalance (QCM) biosensor.

We present a immunosensing system based on a quartz crystal microbalance (QCM) that allows detection and evaluation of a broad range of molecules relevant to medicine and biology. Soluble analyte is applied by injection into a flow-through chamber where receptor molecules are immobilized, thus enabling real-time measurement of the specific intermolecular interactions. This system can be used for detection purposes, e.

An aptamer-based quartz crystal protein biosensor.

We developed a quartz crystal biosensor designed to detect concentrations and ligand affinity parameters of free unlabeled proteins in real time. Using a model system with human IgE as the analyte and single-stranded DNA aptamers or an anti-IgE antibody as immobilized ligands, we could demonstrate that aptamers were equivalent to antibodies in terms of specificity and sensitivity. Both receptor types selectively detected 0.

The VP1-unique region of parvovirus B19: amino acid variability and antigenic stability.

The unique region of structural protein VP1 of parvovirus B19 (erythrovirus B19) is important for eliciting neutralizing antibodies that are responsible for eliminating the virus from the peripheral blood and for inducing lifelong immunity. Neutralizing human MAbs bind a conformationally defined epitope spanning VP1 residues 30-42. The DNA sequence encoding the VP1-unique region was determined in parvovirus B19 isolated from peripheral blood and amniotic fluid of nine acutely infected pregnant women, five arthritis patients and two chronically infected children.