Immobilization studies of an engineered arginine-tryptophan rich peptide on a silicone surface with antimicrobial and anti-biofilm activity
Kaiyang Lim , Ray Rong Yuan Chua , Rathi Saravanan , Anindya Basu , Biswajit Mishra , Paul Anantharajah Tambyah , Bow Ho , and Susanna Su Jan Leong
ACS Appl. Mater. Interfaces, Just Accepted Manuscript
DOI: 10.1021/am401629p
Publication Date (Web): June 12, 2013
Copyright © 2013 American Chemical Society

With rapid rise of antibiotic resistant device associated infections, there is an increasing demand for an antimicrobial biomedical surface. Synthetic antimicrobial peptides that have excellent bactericidal potency and negligible cytotoxicity, are promising targets for immobilization on these target surfaces. An engineered arginine-tryptophan rich peptide (CWR11) was developed, which displayed potent antimicrobial activity against a broad spectrum of microbes via membrane disruption, and possessed excellent salt resistance properties. A tethering platform was subsequently developed to tether CWR11 onto a model polymethylsiloxane (PDMS) surface using a simple and robust strategy. Surface characterization assays such as attenuated total reflectance fourier transform infrared spectroscopy (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDX) confirmed the successful grafting of CWR11 onto the chemically treated PDMS surface. The immobilized peptide concentration was 0.8±0.2 μg/cm2 as quantitated by sulfosuccinimidyl-4-o-(4,4-dimethoxytrityl) butyrate (sulfo-SDTB) assay. Antimicrobial assay and cytotoxic investigation confirmed that the peptide-immobilized surface has good bactericidal and anti-biofilm properties, and is also non-cytotoxic to mammalian cells. Tryptophan-arginine rich antimicrobial peptides have the potential for antimicrobial protection of biomedical surfaces and may have important clinical applications in patients.