Alanine aminotransferase (ALT), also known as serum glutamic-pyruvic transaminase (SGPT), is a crucial enzyme in amino acid metabolism. It catalyzes the transfer of an amino group from alanine to α-ketoglutarate, producing glutamate and pyruvate. ALT is primarily found in the liver but is also present in other tissues. Assay kits for ALT are essential in clinical diagnostics and research, serving as markers for liver health and cellular damage.
Principles of ALT Assay Kits
ALT assay kits typically measure enzyme activity through a series of enzyme-driven reactions. The most common methods include:
- Colorimetric Assays: ALT catalyzes the conversion of alanine and α-ketoglutarate into glutamate and pyruvate. Pyruvate is then detected using a colorimetric probe. In some kits, pyruvate reacts with 2,4-dinitrophenylhydrazine (DNPH) to form a reddish-brown phenylhydrazone under alkaline conditions.
- Fluorometric Assays: Similar to colorimetric assays, but pyruvate is detected using a fluorometric probe. The fluorescence is measured at excitation/emission wavelengths around 530-570 nm / 590-600 nm.
Applications of ALT Assay Kits
- Liver Function Assessment: Elevated ALT levels are indicative of liver damage or disease.
- Metabolic Studies: Investigating amino acid metabolism and its impact on cellular health.
- Disease Research: Studying conditions like hepatitis, cirrhosis, and fatty liver disease.
Key Features of ALT Assay Kits
- Sensitivity and Specificity: Kits offer high sensitivity for detecting ALT activity in various sample types, including serum, plasma, and tissue homogenates.
- Ease of Use: Simple protocols with rapid detection methods make these kits accessible for both clinical and research applications.
- Versatility: Suitable for different sample types and can be used in high-throughput screening formats.
Alanine aminotransferase assay kits are vital tools for assessing liver health and understanding amino acid metabolism. By providing precise measurements of ALT activity, these kits support both clinical diagnostics and research into metabolic disorders and liver diseases. The choice between colorimetric and fluorometric methods depends on the specific requirements of the study, including sensitivity and throughput needs.