Infection of medical polymers starts with the initial adhesion of infectious organisms that subsequently grow to form a biofilm. Thus polymer materials which possess inhibiting effect to biofilm formation can reduce infection rate.OBJECTIVE:
To evaluate the antimicrobial efficacy of modified polyethylene samples and the inhibitory effect of antimicrobial agent on biofilm formation on the polyethylene surface.DESIGN, TIME AND SETTING:
A controlled observation experiment in vitro was performed at the State Engineering Research Center of Engineering Plastic, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences (Beijing, China) between January 2007 and January 2008.MATERIALS:
Organic antibacterial agent was triclosan. Inorganic antibacterial agent was ionpure. Low-density polyethylene (LDPE) was used for this study.METHODS:
LDPE was respectively blended with organic antibacterial agent and inorganic antibacterial agent, and the LDPE slice was prepared by injection molding process.MAIN OUTCOME MEASURES:
The antimicrobial efficacy of anti-infective polyethylene was determined by the plate counting method. The ultrasonic-plate method was introduced to observe bacterial density and biofilm formatiom.RESULTS:
Both of modified LDPE samples exhibited excellent antimicrobial performance against S. aureus and E. coli, resulting in a antibacterial rate of 99.9%. The adhesion and propagation of bacteria were evidently reduced by organic antibacterial agent added into LDPE, thereby the formation of biofilm was prevented. The results showed that a large amount of bacteria adhered on the surfaces of LDPE added inorganic antibacterial agent and untreated LDPE.CONCLUSION:
Anti-infective polyethylene added organic antibacterial agent possesses excellent antimicrobial performance against S. aureus and E. coli, and it can inhibit the formation of biofilm on the surfaces.