– For the detection and quantitation of Sulfamethoxazole and related Sulfa compounds in water (groundwater, surface water, well water). For soil, crop, and food use contact the company for application bulletins and/or specific matrix validation guidelines. The Sulfamethoxazole Microtiter Plate Kit applies the principles of enzyme-linked immunosorbent assay (ELISA) to the determination of Sulfamethoxazole. In the assay system, standards, controls, or samples are added, along with an antibody specific to Sulfamethoxazole, to microtiter wells coated with Goat Anti-Rabbit Antibody and incubated for twenty (20) minutes. The Sulfamethoxazole enzyme conjugate is then added. At this point, a competitive reaction occurs between the Sulfamethoxazole, which may be in the sample, and the enzyme-labeled Sulfamethoxazole analog for the antibody binding sites on the microtiter well. The reaction is allowed to continue for forty (40) minutes. After a washing step, the presence of Sulfamethoxazole is detected by adding the Color Solution, which contains the enzyme-substrate (hydrogen peroxide) and the chromogen (3,3’,5,5’- tetramethylbenzidine). The enzyme-labeled Sulfamethoxazole bound to the Sulfamethoxazole antibody catalyzes the conversion of the substrate/chromogen mixture to a colored product. The color reaction is stopped and stabilized after a thirty (30) minute incubation period by the addition of diluted acid (stopping solution). The color is then evaluated using an ELISA reader. A dose-response curve of absorbance vs. concentration is generated using results obtained from the standards. The concentration of Sulfamethoxazole present in the control and samples is determined directly from this curve. Since the labeled Sulfamethoxazole (conjugate) was in competition with the unlabeled Sulfamethoxazole (sample) for the antibody sites, the intensity of the color developed is inversely proportional to the concentration of Sulfamethoxazole present in the sample.