Absolute Quantification of Proteins and Peptides by ICP-MS
November 01, 2016
Despite all of the recent advances in analytical technologies dedicated to biotherapeutics, accurate protein quantification remains a challenge for the biopharmaceutical industry. UV spectrophotometry is commonly used for batch testing, but it requires the knowledge of the extinction coefficient of the protein, whose experimental determination requires the accurate concentration of a reference standard obtained by an absolute quantification method. To address the need for a fast analytical method capable of accurately quantifying a protein without any specific reference substance, an isotope dilution ICP-MS method was developed and validated, based on sulfur determination, allowing very accurate determination of a single protein in solution after microwave digestion.