Determination of Recombinant Protein Drug Concentration

Recombinant protein drugs refer to protein products derived from animals or plants and developed through biotechnology research. These proteins possess certain biological activities and can prevent, treat, and diagnose diseases in humans, animals, and plants. Compared to small molecule drugs, protein drugs have advantages such as high activity, high specificity, and low toxicity, making them highly favored by researchers. Currently, protein drugs are widely used in various fields, including cancer, autoimmune diseases, metabolic diseases, geriatric diseases, and degenerative diseases.

 

In the process of preparing and using recombinant protein drugs, protein concentration analysis is an essential step. The protein concentration can reflect the efficacy and safety of the drug, and it is of great significance for drug research, production, and use. Common methods for protein concentration analysis include the Bradford method, the Lowry method, the BCA method, and the ultraviolet absorption spectroscopy method.

 

The Bradford method is a protein concentration determination method based on dye binding. This method is quick, convenient, and less prone to interference from other substances, but it is relatively sensitive to the type and structure of the protein. The Lowry method is a traditional protein concentration determination method with high sensitivity, but it involves many steps and is relatively complex to operate. The BCA method, also known as the bicinchoninic acid method, is similar in principle to the Lowry method. The BCA method is relatively simple to operate and is less susceptible to interference from other substances, although it is also somewhat sensitive to the type and structure of the protein. The ultraviolet absorption spectroscopy method for proteins is based on the strong absorption characteristic of aromatic amino acids at 280 nm. The advantage of this method is that it is fast and does not require any chemical reagents, but it requires knowledge of the protein's composition and sequence to accurately calculate the molar extinction coefficient.