Protein quantification can refer to the measurement of the total amount of protein in a given sample or the measurement of a specific protein in a sample. With total protein measurement there are a number of standardised methods available in kits including the Bradford assay and the Lowry assay. The more challenging assay is to measure a protein of interest in a complex mixture. This is typically done by ELISA assay but recent advances in Bio-Layer interferometry technology have allowed the quantification of proteins on of interest in as little as 4ul in 30seconds. This revolutionary technology can be used in many applications to monitor protein production, optimise protein purification and to replace an ELISA assay using less sample and reagents in a fraction of the time.