The aim of this study was to validate a new method for determining benzodiazepines in urine via their benzophenone derivatives, based on liquid chromatography-tandem mass spectrometry (LC-MS/MS). Selected benzodiazepines were analysed after acid hydrolysis of urine and extraction by ethyl acetate in the presence of an internal standard. Samples were analysed using electrospray ionization LC-MS/...

Complement-mediated release of enzyme molecules from reversed-phase evaporation vesicles serves as the basis of the sensitive homogeneous immunoassay reported here. We found it necessary to co-entrap the substrate glucose 6-phosphate with the bacterial enzyme glucose-6-phosphate dehydrogenase (EC 1.1.1.49) to protect enzyme activity during liposome preparation. Enzyme can be released specifical...

Common-path differential phase-contrast interferometry measures the spatial gradient of surface dipole density on a bio-optical compact disk (BioCD) and is sensitive to small changes in dipole density following molecular binding of target molecules out of solution. The recognition molecules are antibody IgG proteins that are deposited in periodic patterns on the BioCD using soft lithography or ...

An ELISA method was developed for the measurement of toxoplasma IgG antibodies in human serum using antigen-coated polystyrene beads as a solid phase and anti human IgG-horse radish peroxidase conjugate as an enzymatic tracer. In order to assess ELISA sensitivity and specificity, a between methods comparison was made using 'conventional' serological tests as reference (dye-test, crossover-linke...

background: since the introduction of the first radioimmunoassay, several improvements have been made in the design of immunoassays such as method of antibody production, labeling, automation and detection technology. we performed an analytical evaluation of the new electrochemiluminescent immunoassay (eclia) for serum tsh, ft4 and t3 in the elecsys 2010 immunoassay system and compared the resu...

background: aflatoxin b1 (afb1) is a toxic metaboliteproduced by aspergillus species that contaminates a wide range ofagricultural products. objectives: this study was designed todevelop a rapid and highly sensitive immunoassay method inmicroarray format for quantitative detection of afb1 to evaluatethe potential of microarray platform for high-throughput screening,which can be beneficial in fo...