Discovering the Future of Microwaves in Bioscience
Michael J. Collins, PhD
President & CEO
CEM Corporation, USA

The past five years has seen an emergence of new applications for microwave science that push the boundaries of classical microwave assisted synthesis, with microwave solid phase peptide synthesis (SPPS) being at the forefront. Microwave SPPS provides peptides faster and in better purity as compared to conventional methods. In addition, microwave energy has allowed the synthesis of certain peptides that are not possible using conventional methods. We have demonstrated that side reactions including aspartimide formation and racemization can be limited in the microwave using our optimized reaction conditions. Our research focus has now turned to pushing the limits of microwave SPPS and expanding its applications to a variety of different types of peptides. This paper will describe some of our recent results in this area including the synthesis of peptides incorporating sterically hindered amino acids and the synthesis of challenging peptide sequences.

Another area of microwave research that is receiving increasing attention over the past couple of years is microwave assisted proteomics, and more specifically, microwave assisted enzymatic digestion of proteins for proteomic analysis. Higher efficiency digestion is obtained for trypsin in 15 minutes using microwaves compared to conventional overnight digestion at 37 °C. This is reflected in higher database search score results as well as higher intensity signals. The method has been applied successfully with solution and in-gel samples and is compatible with a range of enzymes including trypsin, Lys-C, and chymotrypsin. Our latest results as well as an in-depth analysis into the actual basis of the enhanced search scores will be presented in detail.

The future of microwaves in bioscience is limitless, and one area we plan to investigate is the application of microwaves to protein folding. We will present a theoretical approach to how microwave energy can be used to affect the various folded and unfolded states of the protein folding process to rapidly reach the lowest energy state.