title: Antimicrobial polypeptide multilayer nanocoatings.
abstract: A multilayer coating (or film) of nanometer-thick layers can be made by sequential adsorption of oppositely charged polyelectrolytes on a solid support. The method is known as layer-by-layer assembly (LBL). No special apparatus is required for LBL and nanofilms can be prepared under mild, physiological conditions. A multilayer nanofilm in which at least one of the constituent species is a polypeptide is a polypeptide multilayer nanofilm. The present work was aimed at assessing whether polypeptide multilayer nanofilms with specific antimicrobial properties could be prepared by incorporation of a known antimicrobial agent in the film structure, in this case the edible protein hen egg white lysozyme (HEWL). The chicken enzyme is widely employed as a human food preservative. An advantage of LBL in this context is that the nanofilm is fabricated directly on the surface of interest, eliminating the need to incorporate the antimicrobial in other packaging materials. Here, nanofilms were made of poly(L-glutamic acid) (PLGA), which is highly negatively charged in the mildly acidic pH range, and HEWL, which has a high net positive charge at acidic pH. We show that PLGA/HEWL nanofilms inhibit growth of the model microbe Microccocus luteus in the surrounding liquid medium. The amount of HEWL released from PLGA/HEWL films depends on the number of HEWL layers and therefore on the total quantity of HEWL in the films. This initial study provides a sketch of the scope for further development of LBL in the area of antimicrobial polypeptide multilayer films. Potential applications of such films include strategies for food preservation and coatings for implant devices.
authors.affiliation: Biomedical Engineering, Bionanosystems Engineering Laboratory, Center for Applied Physics Studies, PO Box 10348, Louisiana Tech University, Ruston, LA 71272, USA.
authors.forename: Jai S
authors.initials: JS
authors.lastname: Rudra
authors.forename: Komal
authors.initials: K
authors.lastname: Dave
authors.forename: Donald T
authors.initials: DT
authors.lastname: Haynie
mesh_terms: D000900:Anti-Bacterial Agents / Q000138:chemical synthesis* / Q000494:pharmacology; D000890:Anti-Infective Agents / Q000138:chemical synthesis*; D019344:Lactic Acid; D016982:Micrococcus luteus / Q000187:drug effects; D049329:Nanostructures; D010455:Peptides / Q000138:chemical synthesis; D011100:Polyglycolic Acid; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011108:Polymers
chemical_list: D000900:Anti-Bacterial Agents; D000890:Anti-Infective Agents; D010455:Peptides; D011108:Polymers; D000077182:Polylactic Acid-Polyglycolic Acid Copolymer; D011100:Polyglycolic Acid; D019344:Lactic Acid