Development of infection resistant polyurethane biomaterials using textiledyeing technology

Infection is a major complication when using biomaterials such as polyureth ane in the clinical setting. The purpose of this study was to develop a nov el infection resistant polyurethane biomaterial using textile dyeing techno logy. This procedure results in incorporation of the antibiotic into the po lymer, resulting in a slow, sustained release of antibiotic from the materi al over time, without the use of exogenous binder agents. Polycarbonate bas ed urethanes were synthesized that contained either a non-ionic (bdPU) or a nionic (cPU) chain extender within the polymer backbone and cast into films . The fluoroquinolone antibiotic ciprofloxacin (Cipro) was applied to bdPU and cPU using textile dyeing technology, with Cipro uptake determined by ab sorbance reduction of the "dyebath." These dyed bdPU/cPU samples were then evaluated for prolonged Cipro release and antimicrobial activity by means o f spectrophotometric and zone of inhibition assays, respectively. Cipro rel ease and antimicrobial activity by dyed cPU segments that were aggressively washed persisted over 9 days, compared with dyed bdPU and dipped cPU contr ol segments that lasted < 24 hours. Dyed cPU segments, which remained in a static wash solution, maintained antimicrobial activity for 11 days (length of study), whereas controls again lost antimicrobial activity within 24 ho urs. Thus, application of Cipro to the cPU polymer by means of dyeing techn ology results in a slow sustained release of antibiotic with persistent bac teriocidal properties over extended periods of time.