A coating having an adhesive hydrophilic polymer and an amphiphilic additive. The amphiphilic additive has a hydrophilic chain, a biocidal functional group bonded to the hydrophilic chain, and a hydrophobic moiety bonded to the hydrophilic chain or to the biocidal functional group. A method of forming a biocidal surface by providing an article, and coating the article with the above coating. A compound having the formula: Y—(O—CH2—CH2)n—R—(CH2)m—CH3. Y is CH3 or H. R is X is a halogen, and m and n are independently selected positive integers.