Secondary Structure Determination of Peptides and Proteins After Immobilization

The presentation of immobilized peptides and other small biomolecules attached to surfaces can be greatly affected by the attachment chemistry and linking moieties, resulting in altered activity and specificity. For this reason, it is critical to understand how the various aspects of surface immobilization-underlying substrate properties, tether structure, and site of linkage-affect the secondary and quaternary structures of the immobilized species. Here, we present methods for attaching cysteine-containing peptides to quartz surfaces and determining the secondary structure of surface-immobilized peptides. We specifically show that, even when covalently immobilized, changes in peptide conformation can still occur, with measurement occurring in real time.