Antimicrobial peptides (AMPs) have the ability to penetrate as well as transport cargo across bacterial cell membranes, and they have been labeled as exceptional candidates to function in drug delivery. The aim of this study was to investigate the effectiveness of novel formulation of AMPs for enhanced MRSA activity. The strategy was carried out through the formulation of liposomes by thin-layer film hydration methodology, containing phosphatidylcholine, cholesterol, oleic acid, the novel AMP, as well as vancomycin (VCM). Characterization of the AMPs and liposomes included HPLC and LCMS for peptide purity and mass determination; DLS (size, polydispersity, zeta potential), TEM (surface morphology), dialysis (drug release), broth dilution, and flow cytometry (antibacterial activity); MTT assay, haemolysis and intracellular antibacterial studies. The size, PDI, and zeta potential of the drug-loaded AMP₂-Lipo-1 were 102.6 ± 1.81 nm, 0.157 ± 0.01, and − 9.81 ± 1.69 mV, respectively, while for AMP₃-Lipo-2 drug-loaded formulation, it was 146.4 ± 1.90 nm, 0.412 ± 0.05, and − 4.27 ± 1.25 mV respectively at pH 7.4. However, in acidic pH for both formulations, we observed an increase in size, PDI, and a switch to positive zeta potential, which indicated the pH responsiveness of our liposomal systems. The in vitro drug release studies demonstrated that liposomal formulations released VCM-HCl at a faster rate at pH 6.0 compared to pH 7.4. In vitro antibacterial activity against S. aureus and MRSA revealed that liposomes had enhanced activity at pH 6 compared to pH 7.4. The study revealed that the formulation can potentially be used to enhance activity and penetration of AMPs, thereby improving the treatment of bacterial infections.

抗菌肽（AMPs）具有穿透细菌细胞膜以及在细菌细胞膜上运输货物的能力，并且它们被标记为在药物递送中起作用的特殊候选物。本研究的目的是研究新型AMPs制剂对增强MRSA活性的有效性。该策略通过采用薄膜水化方法配制脂质体来实施，其中包含磷脂酰胆碱，胆固醇，油酸，新型AMP和万古霉素（VCM）。AMP和脂质体的表征包括用于肽纯度和质量测定的HPLC和LCMS；DLS（大小，多分散性，ζ电势），TEM（表面形态），透析（药物释放），肉汤稀释和流式细胞仪（抗菌活性）；MTT分析，溶血和细胞内抗菌研究。₂ -Lipo-1分别为102.6±1.81 nm，0.157±0.01和-9.81 ±1.69 mV，而对于AMP ₃ -Lipo-2载药配方，其为146.4±1.90 nm，0.412±0.05和-在pH 7.4时分别为4.27±1.25 mV。但是，在两种配方的酸性pH值中，我们都观察到尺寸，PDI的增加以及向正Zeta电位的转换，这表明我们脂质体系统的pH响应能力。体外药物释放研究表明，脂质体制剂在pH 6.0时以比pH 7.4更快的速率释放VCM-HCl。对金黄色葡萄球菌的体外抗菌活性MRSA和MRSA表明，与pH 7.4相比，脂质体在pH 6时具有增强的活性。研究表明，该制剂可潜在地用于增强AMPs的活性和渗透性，从而改善细菌感染的治疗。