Controlling Surface-Immobilized Elastin-like Peptides for Electrochemical Sensing Applications

Surface-immobilized elastin-like peptides (ELPs), known for their stimuli-responsive behavior, represent a promising biomolecular platform for electrochemical sensing. Key to the success of this applications is understanding how ELPs assemble on electrode surfaces, how the assembly and configuration can be controlled, and how their structure impacts the accessibility of the solid surface to redox active species. Here, we share recent work where short ELPs with varying guest residues and sequence length were designed for gold electrode attachment, and the ability of a redox probe to access a gold surface was characterized by cyclic voltammetry. From these results, a quantitative model describing the relationship between ELP effective surface coverage as a function of the mean hydrophobicity and mass loading was elucidated, illustrating the ability to precisely control surface properties by tuning the ELP sequence. In addition, strategies for controlling surface-bound ELP assembly and properties will be discussed. Ultimately, our work demonstrates that controlling the assembly and ELP configuration on the solid surface leads to more favorable electrochemical sensing capacity.