Albumin Folding Changes Affect the Microfluidic Interfacial Broadening Revealed by Surface Plasmon Resonance

Abstract Understanding the conformation and diffusion behavior of proteins in biological fluids is crucial for advancements in conformational disease research. While several experimental techniques are available for probing protein conformations, they often come with limitations, such as the need for fluorophores or specific experimental conditions. Albumin, one of the most abundant proteins in the blood and used as a tear supplement in treating ocular surface disorders, plays a vital role as a transport protein, binding various ligands and facilitating their transport. However, the direct relationship between albumin conformation and diffusion coefficient ( D ) in water solutions remains unexplored. In this study, we describe a novel Surface Plasmon Resonance technique coupled with Stochastic Gillespie′s algorithm simulations to correlate albumin D values with its conformational states directly. Our findings demonstrate the feasibility of monitoring albumin conformational changes under different environmental conditions, as well as its degradation kinetics by trypsin, by analyzing its diffusion characteristics, presenting a promising avenue for advancing our understanding of conformational diseases.