Loading and Release of Drugs from Oxygen-rich Plasma Polymer Coatings

Low-pressure plasma-polymerized ethylene film coatings rich in bonded oxygen groups (L-PPE:O) were deposited on poly(ethylene terephthalate; PET) in order to act as hosts for antimicrobial drugs. Increasing O2 content in the ethylene (C2H4)/Ardiluted oxygen (O2) gas mixture reduced the deposition rate, but increased the concentration of bonded oxygen, [O], including that of carboxylic acid groups, [?COOH], as determined by X-ray photoelectron- (XPS) and Fourier transform infrared (FTIR) spectroscopies, and by toluidine blue O (TBO) assays. L-PPE:O coatings took up and sustained the release of ciprofloxacin for several hours. Steric hindrance impeded vancomycin penetration into the cross-linked L-PPE:O coatings. Ciprofloxacin-loaded L-PPE:O coatings inhibited in vitro the growth of Staphylococcus aureus. Deposition of L-PPE:O on medical devices may endow them with ability to prevent nosocomial infections.