Tea Stains-Inspired Antifouling Coatings Based on Tannic Acid-Functionalized Agarose

Abstract

It is well-known that tannic acid (TA) and its analogs bind strongly to various substrates to produce, for example, the familiar and unpleasant “tea stains”. Functionalization of a polymer or macromolecule with TA would confer the resulting biomacromolecules with similar binding or anchoring ability on many surfaces. To verify the hypothesis, the naturally occurring polysaccharide agarose (Agr) was functionalized with alkyl bromo moieties, followed by etherification with tannic acid under basic conditions via Williamson ether synthesis. The TA-functionalized Agr (AgrTA) so obtained can be deposited onto titanium (Ti), stainless steel (SS), and silicon surfaces via direct adsorption and intermolecular oxidative cross-linking. The AgrTA-deposited SS surfaces show good stability in flowing electrolytes of varying pH. The AgrTA-deposited SS surfaces can also effectively reduce the adsorption of bovine serum albumin and the adhesion of Escherichia coli and 3T3 fibroblasts. In perhaps what is an ironic twist, t...