L-Kynurenic Acid (Urine) ELISA Assay Kit
L-Kynurenic Acid Urine ELISA Assay Kit manufactured in Germany by Immundiagnostik
Size: 1×96 wells
Standard Range: 1.5-150 µM
Incubation Time: Overnight; 12-18 min
Sample Type: Urine
Sample Size: 50 µL
For Research Use Only
This L-Kynurenic Acid Urine ELISA Assay Kit is designed for the quantitative determination of kynurenic acid. The assay is based on the method of competitive enzyme linked immunoassays. Samples, standards and controls are incubated in wells of a microtiter plate coated with kynurenic acid (antigen), together with a peroxidase labeled polyclonal anti-kynurenic acid antibody. During the incubation period the free target antigen in the sample competes with the antigen immobilized on the wall of the microtiter wells for the binding of the peroxidase-labelled polyclonal antibodies.
After a washing step to removve the unbound components, the peroxidase substrate tetramethylbenzidine (TMB) is added. Finally, the enzymatic reaction is terminated by an acidic stop solution. The colour changes from blue to yellow and the absorbance is measured in the photometer at 450 nm. The intensity of the yellow colour is inverse proportional to the kynurenic acid concentration in the sample; this means, high antigen concentration in the sample reduces the concentration of antibodies bound to the antigen on the plate and lowers the photometric signal. A dose response curve of the absorbance unit (optical density, OD at 450 nm) vs. concentration is generated, using the values obtained from the standards. Kynurenic acid, present in the patient samples, is determined directly from this curve.
Based on internal studies with urine samples of apparently healthy persons, a median of 1.8 µmol/mmol creatinine was measured (n=61). 90% of the values were found to be higher than or equal to 1.3 µmol/mmol creatinine.
We recommend each laboratory to establish its own reference range.