Date of this Version
Post, Jeff. Analysis of Interactions Between Platinum-Containing Drugs and Human Serum Albumin by Using Immunoextraction and Microcolumns. University of Nebraska-Lincoln. 2018.
An immunoextraction method based on affinity microcolumns was developed to study the interactions between platinum-containing anti-cancer drugs and serum transport proteins. The drugs cisplatin, carboplatin, and oxaliplatin were investigated for their binding kinetics with the protein human serum albumin (HSA). A drug/HSA mixture was passed through an affinity microcolumn containing anti-HSA antibodies. The non-protein bound, or free, fraction of the drug in the injected mixture was eluted as a non-retained peak while the HSA and drug-HSA complex were retained. Samples containing the drug or protein alone were also applied to the microcolumn; the results from all of these injections allowed the free fraction of the drug in the drug/protein mixtures to be determined. By measuring the free drug fraction at various times after combining the drug with HSA, it was possible to estimate the association rate constant of each drug for HSA. This approach should be valuable in the analysis of interactions that have slow binding processes, such as those that occur between platinum-containing drugs and HSA. This method could also be extended to other metal-containing drugs and plasma proteins, or for other types of biomolecular interactions with slow binding processes.