A method of reducing a friction coefficient of a surface is disclosed herein, comprising attaching a water-soluble polymer to the surface, and contacting the water- soluble polymer with liposomes, thereby coating the surface with an amphiphilic lipid. Further disclosed herein are solutions comprising a water-soluble polymer attachable to the surface, liposomes, and an aqueous carrier, for reducing a friction coefficient of a surface, and methods utilizing same. Articles of manufacture comprising a substrate coated by a water-soluble polymer which is coated by an amphiphilic lipid are also described, as are uses and methods for treating a synovial joint disorder associated with increased articular friction.