Immobilized Biocides as an Alternative Strategy for Control of Microbial Contamination
Improved antimicrobial vehicles are needed in applications that range from medical biomaterials, cosmetics, and agricultural crop pro tection systems to textile, food packaging, and industrial systems (e.g., carpets). To solve the microbial contamination problem for fabricated parts and medical devices, investigators have explored a variety of con cepts: (1) antibiotic release systems [1-3]; (2) inherent biocidal func tional groups on polymers [4-6]; and (3) metal ion or small ion release systems . Each of these concepts has two key ingredients: a matrix or polymer support and a bioactive agent. These diverse technology concepts can be categorized by one of two general mechanisms. In the first category, the active biocidal function is tightly associated with or conjugated on the material; thus, microbiocidal action must be associ ated with the matrix, and intimate contact between the material and the microorganism is required. In the second category, the biocidal agent is released from the matrix by physical action or by chemical reaction; thus, the microbiocidal action may occur at a site remote or distinct from the origins of the antimicrobial agent because the biocide may diffuse to the site of action. We believe that the immobilization of the antimicrobial agent by covalent bonding has the potential of long term stability, lower toxicity, and longer sustained performance than leach or release-based systems .