at c,* l Eng n, OH

pec t an th e deve c prot delive materials with stability higher than PEG and this has resulted in substantial progress in developing improved materials. There are two major classes of antifouling materials, namely polyhydrophilic and polyzwitterionic materials as summarized in to controlling nonfouling properties. Apart from functional mate-rials, surface packing also plays an important role in achieving nonfouling properties of a surface. Surface coating and modifica-tion methods include physical adsorption via hydrophobic inter-actions or spin-coating [6e8], chemical linkage, self-assembled monolayers (SAMs) [9,10], “grafted-from-surface ” via surface-initiated atom transfer radical polymerization (ATRP) [11,12], “graft-to-surface ” via dipping, cross-linking, or reaction of th