Novel high efficient coatings for anti-microbial surgical sutures using chlorhexidine in fatty acid slow-release carrier systems

PLoS One. 2014 Jul 1;9(7):e101426. doi: 10.1371/journal.pone.0101426. eCollection 2014.

Abstract

Sutures can cause challenging surgical site infections, due to capillary effects resulting in bacteria permeating wounds. Anti-microbial sutures may avoid these complications by inhibiting bacterial pathogens. Recently, first triclosan-resistances were reported and therefore alternative substances are becoming clinically relevant. As triclosan alternative chlorhexidine, the "gold standard" in oral antiseptics was used. The aim of the study was to optimize novel slow release chlorhexidine coatings based on fatty acids in surgical sutures, to reach a high anti-microbial efficacy and simultaneously high biocompatibility. Sutures were coated with chlorhexidine laurate and chlorhexidine palmitate solutions leading to 11, 22 or 33 µg/cm drug concentration per length. Drug release profiles were determined in aqueous elutions. Antibacterial efficacy against Staphylococcus aureus was assessed in agar diffusion tests. Biocompatibility was evaluated via established cytotoxicity assay (WST-1). A commercially triclosan-containing suture (Vicryl Plus), was used as anti-microbial reference. All coated sutures fulfilled European Pharmacopoeia required tensile strength and proved continuous slow drug release over 96 hours without complete wash out of the coated drug. High anti-microbial efficacy for up to 5 days was observed. Regarding biocompatibility, sutures using 11 µg/cm drug content displayed acceptable cytotoxic levels according to ISO 10993-5. The highest potential for human application were shown by the 11 µg/cm chlorhexidine coated sutures with palmitic acid. These novel coated sutures might be alternatives to already established anti-microbial sutures such as Vicryl Plus in case of triclosan-resistance. Chlorhexidine is already an established oral antiseptic, safety and efficacy should be proven for clinical applications in anti-microbial sutures.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Anti-Infective Agents, Local* / chemistry
  • Anti-Infective Agents, Local* / pharmacokinetics
  • Anti-Infective Agents, Local* / pharmacology
  • Chlorhexidine* / chemistry
  • Chlorhexidine* / pharmacokinetics
  • Chlorhexidine* / pharmacology
  • Coated Materials, Biocompatible* / chemistry
  • Coated Materials, Biocompatible* / pharmacokinetics
  • Coated Materials, Biocompatible* / pharmacology
  • Delayed-Action Preparations / chemistry
  • Delayed-Action Preparations / pharmacokinetics
  • Delayed-Action Preparations / pharmacology
  • Enzyme Inhibitors* / chemistry
  • Enzyme Inhibitors* / pharmacokinetics
  • Enzyme Inhibitors* / pharmacology
  • Humans
  • Palmitic Acid* / chemistry
  • Palmitic Acid* / pharmacokinetics
  • Palmitic Acid* / pharmacology
  • Staphylococcus aureus / growth & development*
  • Sutures*

Substances

  • Anti-Infective Agents, Local
  • Coated Materials, Biocompatible
  • Delayed-Action Preparations
  • Enzyme Inhibitors
  • Palmitic Acid
  • Chlorhexidine

Grants and funding

This work was financially supported by the Heraeus Medical GmbH, Wehrheim, Germany (http://www.heraeus-medical.com/de/home_15.html). Within the Klinikum rechts der Isar, Technische Universität München the external funding number was 8895117_HeraeusCoating. This work was supported by the German Research Foundation (DFG) and the Technische Universität München within the funding programme Open Access Publishing. The funder's financial support does not alter the authors' adherence to PLOS ONE policies on sharing data and materials. The funding organization didn't play any role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript and only provided financial support and research materials.