Self-disinfecting plastics for intravenous catheters and prosthetic inserts

Area of Science:

• Materials Science
• Microbiology
• Biomedical Engineering

Background:

• Plastic implants are susceptible to microbial colonization and infection.
• Developing effective strategies to prevent implant-associated infections is crucial.

Purpose of the Study:

• To evaluate the efficacy of incorporating a disinfectant, Irgasan (2,4,4'-trichloro-2'-hydroxydiphenyl ether), into various plastics for preventing microbial infection.
• To assess the antimicrobial activity of Irgasan-impregnated plastics in vitro and in vivo.

Main Methods:

• Disinfectant (Irgasan) was incorporated into ethylvinyl acetate (EVA), polyethylene, polypropylene, and TPX plastics.
• Antimicrobial activity was tested in vitro using agar diffusion assays against Staphylococcus aureus, Staph. epidermidis, Escherichia coli, Proteus mirabilis, and Candida albicans.
• In vivo efficacy was assessed by implanting Irgasan-treated and untreated plastic washers subcutaneously in rabbits, pre-contaminated with Staph. aureus.

Main Results:

• Plastics with 0.2% and 2% Irgasan showed zones of inhibition against tested microorganisms, even after washing.
• 2% Irgasan was required to inhibit Candida albicans, and EVA showed specific inhibition against staphylococci.
• In vivo, all plastics without Irgasan resulted in abscesses, while none of the plastics impregnated with 2% Irgasan did, demonstrating significant protection (P < 0.00001).

Conclusions:

• Incorporating Irgasan into plastic materials is a highly effective method for preventing implant-associated infections.
• This technique offers a significant advancement in reducing the incidence of infections related to medical plastic devices.
• The study demonstrates the potential of antimicrobial-releasing plastics in clinical applications.