β-Lapachone encapsulated into stealth liposomes: inhibition of biofilm and cell wall thickness of MRSA.

Methicillin-resistant Staphylococcus aureus (MRSA) is a biofilm-producing pathogen that causes infections worldwide and is considered a global public health problem. In this scenario, new therapeutic strategies to eliminate this pathogen and eradicate the biofilm are essential. Thus, this study aimed to evaluate the effects of β-lapachone (β-lap) encapsulated into stealth liposomes (β-lap-SL) on biofilm and cell wall thickness of MRSA, as well as their hemotoxicity. β-lap-SL were prepared using the lipid film hydration method and physicochemical characteristics were determined. Antibiofilm activity was measured through the crystal violet staining method, the changes in cell wall thickness of MRSA were verified by transmission electron microscopy, and the biocompatibility of the formulation was assessed by hemolytic assay. β-lap-SL was produced and exhibited particle size of 84.2 ± 8.9 nm, polydispersion index of 0.28, zeta potential of + 0.31 ± 0.06 mV, encapsulation efficiency of 98.7 ± 0.6% and pH of 7.5. The antibiofilm activity of β-lap-SL showed values ​​between 4 and 32 µg/mL, and β-lap-SL inhibits the cell wall thickness (55%). β-lap at 64 µg/mL exhibited high toxicity in erythrocytes (~ 45%) compared to β-lap-SL (< 5%) at the same concentration. Based on the results of this study, β-lap-SL appears as a therapeutic agent, and it is a promising option for controlling MRSA-induced infections.