The Syva Emit® st® Urine Amphetamine Assay qualitatively determines the presence of urine amphetamine, one sample at a time. In each test, one sample and one calibrator are always assayed together to compare the reaction rates. This method is inefficient and expensive. Detailed analysis of the reaction kinetics of the Emit® st® Urine Amphetamine reagents indicated that the reaction kinetics were relatively linear up to 15 minutes after the initiation of the reactions. This makes it possible to assay multiple samples with a single calibrator. A modified protocol is described which analyzed three samples with each calibrator, a modification leading to savings of one-third of the reagents and cost, with no compromise in assay performance. Addition of an extra 2 ml of distilled water to the regular protocol can lead to even more savings.
Lua, A.C.; Chiang, C.K.; and Gu, M.C.
"Modification of the Syva Emit® st® Urine Amphetamine Assay,"
Journal of Food and Drug Analysis: Vol. 2
, Article 1.
Available at: https://doi.org/10.38212/2224-6614.3027