Periodic charge matching driven immobilization of gentamicin in nanoclays for stable and long-term antibacterial coating

Dalton Trans. 2021 Oct 19;50(40):14216-14222. doi: 10.1039/d1dt02540f.

Abstract

Matching of charge periodicity between a guest and a host enabled effective immobilization of highly water-soluble antibiotic drug, gentamicin C, in a bentonite clay by cation exchange. X-ray diffraction, infrared spectroscopy and CHNS analysis revealed the immobilization manner of gentamicin C, which was immobilized between bentonite layers via periodic charge-charge interaction with tilted arrangement, as a trication. Both gentamicin alone and a gentamicin/bentonite hybrid were coated onto a polyurethane substrate using water-borne polyurethane binder. The antibiotic character of both films was investigated as prepared or after immersion in phosphate-buffered saline till 5 days against E. coli and B. subtilis bacteria. It was clearly shown that the gentamicin/bentonite hybrid-coated film showed sustained antibacterial efficacy even after exposure to phosphate-buffered saline, while gentamicin only-coated film gradually lost its performance under the same condition.

MeSH terms

  • Anti-Bacterial Agents / chemistry
  • Anti-Bacterial Agents / pharmacology*
  • Bacillus subtilis / drug effects*
  • Bentonite / chemistry
  • Clay / chemistry*
  • Escherichia coli / drug effects*
  • Gentamicins / chemistry
  • Gentamicins / pharmacology*
  • Microbial Sensitivity Tests
  • Molecular Conformation
  • Nanoparticles / chemistry*
  • Polyurethanes / chemistry

Substances

  • Anti-Bacterial Agents
  • Gentamicins
  • Polyurethanes
  • Bentonite
  • Clay