Acta Vet. Brno 2023, 92: 279-287
Feasible delivery system based on poly(lactictide-co-glycolide) nanoparticles loaded with antimicrobial mupirocin for possible wound healing
The objective of the study was to assess cytotoxicity (based on the dimethylthiazol–diphenyltetrazolium bromide cell viability assay) and antimicrobial effects of poly(lactictide-co-glycolide) nanoparticles with entrapped mupirocin (PLGA/MUP NPs) on Staphylococcus aureus and methicillin-resistant S. aureus (MRSA) strains using a disk-diffusion method, cryo-scanning electron microscopy (cryo-SEM) and fluorescence microscopy. Based on the evaluation of the growth curve, PLGA/MUP NPs inhibited growth of the both tested strains already at a concentration of 0.29 µg/ml, and their inhibitory effect at concentrations from 0.29 to 1.17 µg/ml was comparable with free MUP using the disk-diffusion method. PLGA/MUP NPs also tended to increase the abundance of the dead cells of MRSA, but not of S. aureus, in comparison with free MUP when evaluated by fluorescence microscopy. Further, cryo-SEM evaluation demonstrated an antibacterial-inhibitory effect of PLGA/MUP NPs on S. aureus in a dose-dependent manner. On the other hand, PLGA/MUP NPs cytotoxic activity tended to be substantially lower in comparison with both free MUP and empty PLGA NPs. It can be concluded that the excellent biocompatibility and satisfactory antibacterial effects of PLGA/MUP NPs constitute a suitable alternative as far as cutaneous wound healing is concerned.
Keywords
Cytotoxicity, Staphylococcus aureus, cryo-scanning electron microscopy, fluorescence microscopy, disk-diffusion test.
Funding
This work was supported by the Internal Grant Agency of the Faculty of AgriSciences of the Mendel University in Brno (Project No. AF-IGA2019-TP006) and by the ERDF “Multidisciplinary research to increase application potential of nano-materials in agricultural practice” (Project No. CZ.02.1.01/0.0/0.0/16 025/0007314). The authors also thank Dr. Pavel Svec (Mendel University in Brno) for providing the Cryo-SEM analysis and Dr. Kristyna Smerkova and doc. Sona Hermanova (Mendel University in Brno) for manuscript editing.
