Aspartate Aminotransferase Colorimetric Activity Assay Kit Reference: 701640-96 Cayman’s Aspartate Aminotransferase Colorimetric Activity Assay Kit provides a convenient method of detecting AST activity in serum, plasma, tissue samples, and cell lysates. Measurement of the AST activity is carried out by monitoring the rate of NADH oxidation in a coupled reaction system employing malate dehydrogenase (MDH). The oxidation of NADH to NAD+ is accompanied by a decrease in absorbance at 340 nm. Under circumstances in which the AST activity rate is limiting, the rate of decrease is directly proportional to the AST activity in the sample. Lactate dehydrogenase (LDH) is added to prevent interference from endogenous pyruvate normally present in serum.
Alkaline Phosphatase Colorimetric Activity Assay Kit Reference: 701710-480 Cayman’s Alkaline Phosphatase (ALP) Colorimetric Activity Assay Kit provides a convenient method of measuring ALP activity in serum, plasma, tissue samples, and cell lysates with a limit of detection of 0.5 U/L. Measurement of ALP activity is carried out by monitoring the dephosphorylation of the chromogenic substrate p-nitrophenyl phosphate (pNPP). In the first step, ALP dephosphorylates pNPP generating p-nitrophenol. In the second step, the phenolic hydroxyl group is deprotonated under alkaline conditions resulting in p-nitrophenolate, which yields an intense yellow color that can be measured using absorbance at 405 nm. Under circumstances in which ALP activity is rate limiting, the increase in absorbance at 405 nm is directly proportional to ALP activity in the sample.
Protein Aggregation Fluorometric Assay Kit Reference: 701760-96 Cayman’s Protein Aggregation Assay Kit provides a fast and convenient method to determine the level of protein aggregation in a purified antibody solution or other protein solutions after generating an appropriate standard curve using the protein of interest. The assay uses a Protein Aggregation Dye that binds to exposed hydrophobic regions, resulting in an increase in fluorescence, which can be easily quantified using a fluorescence plate reader at excitation and emission wavelengths of 490 and 550 nm, respectively. Aggregated and unaggregated antibody solutions are included as positive and negative controls, respectively. The limit of the detection of the the assay is less than 1% aggregation.