A method of surface treating surgical dressings and implants to reduce the likelihood of post-operative infection and synthetic, water dispersible lipid constructs for use in the method are disclosed.In a first aspect the invention provides an antimicrobial surface treatment method comprising the step of contacting the surface of an object with an aqueous dispersion of at least one functional-lipid construct where the lipid is a di-acyl, di-alkenyl or di-alkyl glycerophospholipid and the functional moiety of the construct confers the antimicrobial activity.