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Title: Influence of poly‐ l ‐lysine molecular weight on antibacterial efficacy in polymer multilayer films
Abstract

Antibacterial coatings can prevent and treat medical device‐associated infections. We examined the antibacterial properties of coatings assembled from poly‐l‐lysine (PLL) and hyaluronic acid (HA). PLL/HA films were fabricated using layer‐by‐layer assembly with three different PLL MWs, differentiated by number of repeat units, that is, 33, 91, and 407 (denoted by PLL30, PLL90, and PLL400). Films assembled with all three PLL MWs completely inhibited the growth of planktonic, gram‐positiveStaphylococcus aureusand methicillin‐resistantS. aureusand gram‐negativePseudomonas aeruginosaandEscherichia coliover a 24‐h exposure. All three film architectures also inhibitedS. aureusattachment by ~60–70% compared to non‐film‐coated surfaces, likely attributed to significant film hydration and electrostatic repulsion due to HA. The true differences in antibacterial efficacy between different PLL MWs were observed upon repeated exposure of PLL/HA toS. aureusevery 24 h. We found that PLL400films lost the ability to inhibit planktonicS. aureusgrowth after one use while PLL30and PLL90films were effective over 4–5 and 9–13 repeated exposures, respectively. Our experiments indicated that differences in efficacy were related to low in‐film mobility of PLL400and also agreed with dissolution timescales for PLL30and PLL90films. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A: 107A: 1324–1339, 2019.

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NSF-PAR ID:
10461254
Author(s) / Creator(s):
 ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
Journal of Biomedical Materials Research Part A
Volume:
107
Issue:
6
ISSN:
1549-3296
Page Range / eLocation ID:
p. 1324-1339
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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