Inhibition of methicillin-resistant Staphylococcus aureus (MRSA) biofilm by cationic poly (D, L-lactide-co-glycolide) nanoparticles

Abstract

The emergent need for new treatment methods for multi-drug resistant pathogens such as methicillin-resistant Staphylococcus aureus (MRSA) has focused attention on novel potential tools like nanoparticles (NPs). In the present study, a drug-free cationic nanoparticles (CNPs) system was developed and its anti-MRSA effects were firstly investigated. The results showed that CNPs (261.7 nm, 26.1 mv) showed time- and concentration-dependent activity against MRSA growth, killing ∼ 90% of planktonic bacterial cells in 3 h at 400 μg ml⁻¹, and completely inhibiting biofilm formation at 1000 μg ml⁻¹. Moreover, CNPs at 400 μg ml⁻¹ reduced the minimum inhibitory concentration (MIC) of vancomycin on inhibition of planktonic MRSA growth (∼ 25%) and biofilm formation (∼ 50%). The CNPs–bacteria interaction force was up to 22 nN. Overall, these data suggest that CNPs have a good potential in clinical applications for the prevention and treatment of MRSA infection.

Keywords:

• Anti-biofilm
• MRSA
• nanomaterials
• drug tolerance

Disclosure statement

The authors declare no potential conflicts of interest regarding the authorship and/or publication of this article.

Acknowledgement

Thanks to Professor Qun Sun from the College of Life Sciences, Sichuan University for providing the MRSA strain.

Additional information

Funding

This work was supported by grants from the National Natural Science Foundation of China (grant number 31870065, 81402860), a Grant of the Deep Underground Space Medical Center Research Foundation of Sichuan University (No. DUGM201816), the Excellent Young Scientist Foundation of Sichuan University (No. 2016SCU04A02), the Huohuaku Foundation of Sichuan University (No. 2018SCUH0083) and the Foundation of State Key Laboratory of Oral Disease (No. SKLOD201922).