Methods of surface treating tubular medical products

A method of treating a tubular medical device with a biomolecule comprising the steps of:

• a) providing a polyolefin tubular substrate forming a tubular medical device;
• b) cleaning the tubular polyolefin substrate;
• c) exposing the tubular polyolefin substrate to a reactive gas containing at least one of acrylic acid and siloxane and to plasma energy to yield a plasma-deposited coating on at least one surface of the tubular polyolefin substrate, wherein step c) includes the steps of the exposing the polyolefin substrate to a reactive gas containing siloxane functional groups and plasma energy to yield a plasma-deposited polysiloxane surface on the surface of the polyolefin substrate prior to exposing the polyolefin substrate to a reactive gas containing acrylic acid and to plasma energy, and rendering the plasma deposited polysiloxane surface amino functional;
• and
• d) attaching a biomolecule to the polyolefin substrate following formation of the plasma-deposited coating on at least one surface of the tubular polyolefin substrate, and wherein the biomolecule is heparin at least one of an antibacterial agent, antimicrobial agent, anticoagulant, heparin, antithrombotic agent, platelet agent, anti-inflammatory, enzyme, catalyst, hormone, growth factor, drug, vitamin, antibody, antigen, protein, nucleic acid, dye, a DNA segment, an RNA segment, protein, and peptide.