In vitro antibacterial effect of vancomycin hydrogel on methicillin-resistant Staphylococcus aureus.

OBJECTIVE

To evaluate the in vitro antibacterial effect of vancomycin hydrogel on methicillin-resistant Staphylococcus aureus (MRSA).

METHODS

We used polylactide glycolide-polyethylene glycol-polylactide glycolide (PLGA-PEG-PLGA) copolymer as a carrier of vancomycin to prepare vancomycin hydrogel. A vancomycin hydrogel group, a PLGA-PEG-PLGA copolymer group, a phosphate-buffered saline (PBS) negative control group and a vancomycin group were set for comparison. Then, we analyzed the in vitro antibacterial effect of each group to determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) and to evaluate the effect of vancomycin hydrogel on the cell activity of bacterial biofilms.

RESULTS

The temperature of the successfully prepared PLGA-PEG-PLGA vancomycin copolymer was slightly lower than normal body temperature. The copolymer reduced both MIC (1 μg/mL) and MBC (2 μg/mL) for MRSA by 1 time. Compared with phosphate buffered saline negative control group and PLGA-PEG-PLGA copolymer group, the MIC vancomycin and vancomycin hydrogel groups showed a reduction of 3 CFU/mL (P<0.05) on the inhibitory effect of original colony count (106 CFU/mL). Though the antibacterial effect of MIC the vancomycin group was significantly better than the vancomycin hydrogel group in the first 12 h, the antibacterial effects of the two were similar after 12 hours. The effect of 1 MIC vancomycin on the cell activity of MRSA biofilm was higher than that of 1 MIC vancomycin hydrogel (P<0.05).

CONCLUSION

Vancomycin hydrogel with a reduced dosage has a similar antibacterial effect to vancomycin. This finding provides a reference for the development of novel sustained-release vancomycin formulations in future treatment of MRSA.