A method is presented for providing a medical device with antibacterial activity, whereby a substrate material coated with a hydrophilic polymer is provided, the hydrophilic polymer exhibiting a low friction when wetted; also provided is a colloidal solution comprising chemically reduced particles of an oligodynamic metal and a hydrophilic polymer, the hydrophilic polymer being the same as in the coating of the substrate material; and the step of dipping the substrate material in the solution. A medical device prepared accordingly is also provided.