Authors: M. Rabe, J. Zimmermann, D. Verdes and S. Seeger
Affilation: University of Zurich, Switzerland
Pages: 500 - 503
Keywords: spectroscopy and imaging, bio sensors
We present a comprehensive mechanistic study of the non-specific adsorption of β-Lactoglobulin on a solid interface by comparing the adsorption kinetics of this protein to theoretical predictions of reported models. Important experimental observations were increasing adsorption rates and overshootings in the beginning of the adsorption as well as a transition to an almost irreversibly bound state of the protein in the long term. Furthermore, rinsing experiments proved that adsorbed proteins abruptly change their desorption behavior from irreversible to reversible when a critical surface coverage is reached. Based on these experimental observations, a mathematical model is proposed confirming many theoretically described phenomena. Since in many applications it is desired to have a control over protein adsorption processes strategies to specifically tailor adsorption properties of surfaces are of great interest. In our approach a straight forward coating procedure was applied to grow silicone nano-filaments on glass coverslips resulting in a very high surface roughness. After chemical modification with amino and carboxyl groups the surfaces perfectly mimic stable anionic or cationic exchange resins. Thanks to the high surface area of the randomly coiled nano-filaments and the ease of their fabrication these surfaces show a potential in the fields of chromatography and biochip technology.