부산대학교 도서관

The aim of this study was to characterize the antimicrobial and antibiofilm activities of ciprofloxacin (CIP) and rifampicin (RMP) loaded on a calcium alginate (CaAlg) scaffold via electrostatic interaction of CaAlg/antibiotic (s) and chitosan-TPP nanoparticles (Cs-TPP NPs). The identification of the shape and functional groups was carried out using scanning electron microscope (SEM) and Fourier transform infrared (FT-IR) spectroscopy. SEM images show that the nanoparticles are spherical and granular with an average size of about 100–500 nm. FT-IR results revealed bonds that corresponded to the Cs-TPP NPs and CaAlg-antibiotics (CaAlg-CIP, CaAlg-RMP) after the loading process. The tube adherence method (TM) was employed to identify potential biofilm producers. The antibiofilm capacity of Cs/CaAlg-CIP and Cs/CaAlg-RMP as well as free antibiotics was used against clinical strains in a test tube method and the results showed that the use of sub-MICs of nanodrugs (1/2 MIC) inhibited biofilm formation in the tested strains compared to free CIP and RMP (P < 0.05). The potential antimicrobial effects of Cs/CaAlg-CIP and Cs/CaAlg-RMP NPs against clinical strains were also evaluated using the minimum inhibitory concentration (MICs) and a time-dependent killing method. A robust inhibitory effect on bacterial growth was observed even at low concentrations of Cs/CaAlg-CIP and Cs/CaAlg-RMP NPs (CONC 4 and 2 μg.mL─1) compared to free drugs (CIP at 32 and RMP at 8.0 μg.mL─1), (P < 0.05). The kinetics assay indicated that the Cs/CaAlg-CIP and Cs/CaAlg-RMP NPs had faster and lasting antibacterial effects than those of the free drug(s) on the tested strains. This study shows that loading CIP and RMP into CaAlg scaffolds and complexes with chitosan-TPP nanoparticles via the emulsification/internal gelation increases the antimicrobial activity of antibiotics against clinical strains of S. aureus and thus might serve as a novel type of antimicrobial compounds for the treatment of bacterial infections.