The bicinchoninic acid (BCA) assay is a colorimetric assay that measures protein concentration in a sample based on a chemical reaction that causes a change of colour. Peptide bonds and certain amino acids such as cysteine, tryptophan, and tyrosine enable the reduction of cupric ions (Cu2+) to cuprous ions (Cu+) in an alkaline medium, also known as the biuret reaction. The resulting cuprous ions then react with the sodium of two bicinchoninic acids to generate a purple colour, the purple complexThe dataset above presents the optical density from the purple complex of PLGA nanoparticles measured following the conjgation of the antibody to the polymeric particles along with its intermediary state (NHS-PLGA).