Quantifying and understanding protein adsorption to non-fouling surfaces

Surfaces grafted with poly(ethylene oxide) (PEO) are known to resist protein adsorption. Research efforts in this field have focused on both developing surfaces with better resistance to protein adsorption and understanding the origin of resistance of PEO grafted surfaces to protein adsorption. In the first part of this contribution, we describe a novel quantification technique for extremely low protein coverage on surfaces. This technique utilizes measurement of the landing rate of microtubule filaments on kinesin proteins adsorbed on a surface to determine the kinesin density. The detection limit of our technique is 100 times lower than that of standard characterization methods and is employed to test the performance of novel and established coatings with outstanding resistance to protein adsorption. In the second part, a random sequential adsorption (RSA) model is presented for protein adsorption to PEO coated surfaces. The model suggests that PEO chains act as almost perfect steric barriers to protein adsorption. Furthermore, it can be used to predict the performance of a variety of systems towards resisting protein adsorption and can help in the design of better non-fouling surface coatings.