In response to injury, blood coagulation is activated and results in generation of the clotting protease, thrombin. Thrombin cleaves fibrinogen to fibrin which forms an insoluble clot that stops hemorrhage. Factor V (FV) in its activated form, FVa, is a critical cofactor for the protease FXa and accelerator of thrombin generation during fibrin clot formation as part of prothrombinase (1, 2). Ma...

Two simple enzyme immunoassays, a conventional microplate and dot-ELISA, were developed to detect specific IgM antibodies using pool sonicated antigen prepared from three of the most reactive serovars of Leptospira associated with disease in Thailand. Both assays were evaluated and compared with the standard microscopic agglutination test (MAT) performed with 343 serum samples. A battery of 16 ...

The TopCountTM Microplate Scintillation Counter quantitates radioisotopes by liquid scintillation counting in standard microplate formats. Assays that previously had to be transferred from microplates to vials or to non-standard formats for counting can now be quantitated directly in microplates. TopCount can count up to 12 samples simultaneously with performance comparable to that of discrete ...

Microplate reader assays offer several advantages over conventional spectrophotometric assays. We adapted the dihydrofolate reductase (DHFR) enzyme inhibition assay for use in a 96-well microplate reader to measure plasma methotrexate (MTX) concentrations. The assay is linear from 0.01 to 0.1 micromol/L. The within-run CVs at 0.03 micromol/L and 0.08 micromol/L MTX were 4.0% and 2.7%, respectiv...

The TopCountTM Microplate Scintillation Counter quantitates radioisotopes by liquid scintillation counting in standard microplate formats. Assays that previously had to be transferred from microplates to vials or to non-standard formats for counting can now be quantitated directly in microplates. TopCount can count up to 12 samples simultaneously with performance comparable to that of discrete ...

Here, we present a Microsoft Windows application that has been written to emulate a microplate reader. After scanning a standard 96-well microplate, color gradations in the slots can be analyzed quantitatively and be used for the estimation of enzyme kinetics, binding assays or concentration determination. In a test, series accuracy of the program was determined. We show that the returned optic...

The trend towards assay miniaturization for high-throughput and ultra-high-throughput screening continues to spur development of homogeneous, fluorescence-based assays in higher density, smaller volume microplate formats. Recently, first-generation microfluidic devices have been designed for performing continuous-flow biochemical and cell-based assays. These devices provide orders-of-magnitude ...