In protein analysis, the Alkaline Copper Solution is primarily used to form complexes with proteins, which can then be quantified through __________.

The Alkaline Copper Solution reacts with peptide bonds in proteins to create a violet copper‑protein complex. This color change is directly proportional to protein concentration. By measuring the intensity of the violet color with a spectrophotometer, the amount of protein can be calculated. Thus, the complexes are quantified through spectrophotometry. For example, a sample that turns deep violet will show a higher absorbance at 540 nm, indicating a higher protein level.