Alanine Aminotransferase Activity Assay Kit

Alanine aminotransferase (ALT) is a pyridoxal phosphate-dependent enzyme predominantly found in the liver. It catalyzes the reversible transamination between alanine and α-ketoglutarate to form pyruvate and glutamate, playing a vital role in amino acid metabolism and gluconeogenesis. Under normal conditions, serum ALT levels are low; however, hepatocyte damage increases membrane permeability, releasing ALT into the bloodstream. Since even 1% hepatic injury can double serum ALT levels, it serves as a highly sensitive and specific biomarker for liver function and cellular damage.

This kit provides a sensitive, rapid, and simple method for detecting ALT activity. The assay utilizes ALT to generate pyruvate, which is subsequently converted to hydrogen peroxide (H₂O₂) by pyruvate oxidase. In the presence of horseradish peroxidase, H₂O₂ reacts with Amplex Red to produce the highly fluorescent product resorufin. The fluorescence intensity or absorbance of resorufin is proportional to ALT activity. This assay is suitable for serum, plasma, tissues, and cells.

Figure 1. Typical standard curve and assay data. (A) Reference standard curve obtained via colorimetric detection. (B) Reference standard curve obtained via fluorometric detection. (C) Measurement of ALT activity in various samples using this kit.