Amplite® Colorimetric BCA Protein Quantitation Assay Kit is a colorimetric assay for quantifying total protein concentration in biological samples. It is based on the reduction of Cu²⁺ to Cu⁺ by peptide bonds under alkaline conditions, followed by the chelation of Cu⁺ with bicinchoninic acid (BCA) to form a stable purple complex. The intensity of the color, measured at 562 nm, is directly proportional to protein concentration. This two-step reaction provides a robust and detergent-compatible assay format. The BCA assay offers a broader detection range and greater stability than traditional Bradford assays, with less variability due to differences in amino acid composition. It is ideal for quantifying proteins in lysates, extracts, or purified preparations, and can be read using a standard microplate reader or spectrophotometer.