Optimization and Characterization of Aspirin Encapsulated Nano-liposomes

Resistance to aspirin and its cytotoxicity significantly limits its therapeutic applications. Nano-liposomal encapsulation of aspirin can reduce its cytotoxicity. In this study, aspirin encapsulating nano-liposomes (AS-NL) was prepared and its performance in drug delivery and also cytotoxicity was evaluated. The effects of two independent variables including number of freeze/thawing cycles and concentration of aspirin on encapsulation efficiency was investigated using response surface methodology (RSM). A drug profile release was obtained by AS-NL. The concentration of cholesterol as effective for liposome stability and sodium lauryl sulfate (SLS) as a drug release facilitator was also optimized using RSM. The maximum aspirin encapsulation efficiency (41.44%) and drug release (33.92%) was obtained for 0.514 mg cholesterol and 0.007 mg SLS used for liposome formulation. The morphology and size of AS-NLs were characterized using transmission electron microscopy (TEM) and dynamic light scattering (DLS). The stability of AS-NL was evaluated by measuring the size change of nano-liposomes during 21 days using DLS analysis. The stability of AS-NL during this period was acceptable. The cytotoxicity test of AS-NL by MTT test reveals the cytotoxicity of aspirin can be reduced by using liposome encapsulation.