Evaluation of bacterial uptake, antibacterial efficacy against Escherichia coli, and cytotoxic effects of moxifloxacin-loaded solid lipid nanoparticles

Arh Hig Rada Toksikol. 2022 Dec 30;73(4):260-269. doi: 10.2478/aiht-2022-73-3667. eCollection 2022 Dec 1.

Abstract

Moxifloxacin (MOX) is an important antibiotic commonly used in the treatment of recurrent Escherichia coli (E. coli) infections. The aim of this study was to investigate its antibacterial efficiency when used with solid lipid nanoparticles (SNLs) and nanostructured lipid carriers (NLCs) as delivery vehicles. For this purpose we designed two SLNs (SLN1 and SLN2) and two NLCs (NLC1 and NLC2) of different characteristics (particle size, size distribution, zeta potential, and encapsulation efficiency) and loaded them with MOX to determine its release, antibacterial activity against E. coli, and their cytotoxicity to the RAW 264.7 monocyte/macrophage-like cell line in vitro. With bacterial uptake of 57.29 %, SLN1 turned out to be significantly more effective than MOX given as standard solution, whereas SLN2, NLC1, and NLC2 formulations with respective bacterial uptakes of 50.74 %, 39.26 %, and 32.79 %, showed similar activity to standard MOX. Cytotoxicity testing did not reveal significant toxicity of nanoparticles, whether MOX-free or MOX-loaded, against RAW 264.7 cells. Our findings may show the way for a development of effective lipid carriers that reduce side effects and increase antibacterial treatment efficacy in view of the growing antibiotic resistance.

Moksifloksacin je važan antibiotik koji se često rabi za liječenje rekurentne infekcije bakterijom Escherichia coli (E. coli). Cilj je ovog istraživanja bio ocijeniti njegovu djelotvornost u formulaciji s krutim lipidnim nanočesticama (engl. solid lipid nanoparticles, krat. SNL) i nanostrukturiranim lipidnim nosačima (engl. nanostructured lipid carriers, krat. NLC) kao njegovim vehikulima. U tu smo svrhu osmislili dva SLN-a (SLN1 i SLN2) te dva NLC-a (NLC1 i NLC2) različitih svojstava (veličine čestice, raspodjele veličina, zeta potencijala i sposobnosti enkapsulacije) te ih obogatili moksifloksacinom kako bismo utvrdili njegovo otpuštanje, djelovanje protiv E. coli i citotoksičnost za makrofagnu staničnu liniju RAW 264.7 in vitro. S bakterijskom apsorpcijom od 57,29 %, SLN1 se pokazao značajno djelotvornijim vehikulom moksifloksacina od njegove standardne formulacije (otopine), a formulacije s SLN2, NLC1 odnosno NLC2 s odgovarajućim apsorpcijama od 50,74 %, 39,26 % odnosno 32,79 % iskazale su djelotvornost sličnu onoj standardnog antibiotika. Test citotoksičnosti nije pokazao značajnu toksičnost nanočestica bez obzira na to jesu li sadržavale moksifloksacin ili nisu. Naši rezultati upućuju na mogući smjer razvoja djelotvornih lipidnih nosača kojima bi se mogle smanjiti nuspojave i povećati antibakterijska djelotvornost liječenja s obzirom na sve veću bakterijsku rezistentnost.

Keywords: E. coli; RAW 264.7 cell line; antibiotic; antibiotik; biocompatibility; biokompatibilnost; drug resistance; lipid-based nanoparticles; nanočestice s lipidima; rezistentnost na lijek; stanična linija RAW 264.7.

MeSH terms

  • Anti-Bacterial Agents / toxicity
  • Antineoplastic Agents*
  • Drug Carriers
  • Escherichia coli
  • Lipids
  • Moxifloxacin / pharmacology
  • Nanoparticles* / toxicity

Substances

  • Lipid Nanoparticles
  • Moxifloxacin
  • Drug Carriers
  • Antineoplastic Agents
  • Anti-Bacterial Agents
  • Lipids