The BCAA-Glo™ Assay is a fast and sensitive method for detecting branched-chain amino acids (BCAA; leucine, isoleucine and valine) from various biological samples, such as cultured cells, media, tissue homogenates and serum. Based on bioluminescent technology, the BCAA-Glo™ Assay can detect subtle changes in amino acid metabolism and abundance. Its streamlined sample preparation protocol involves acid treatment and neutralization directly in the assay wells, eliminating the need for cell collection, centrifugation and spin columns. The assay is adaptable to a 384-well format, facilitating quick analysis of many samples.