Liposome stability assay

The dialysis technique was used to evaluate the in vitro stability of the liposomal formulations in PBS pH 7.4% and 50% FBS at 37°C over a 48 hours duration, as previously described.22 A modified assay was used to evaluate the true release of each drug from the liposomes without surpassing saturation point, which addressed the potential solubility issues across the dialysis membrane. Drug retention percentage was determined by: Drug retention (%) = 100% − [(D_t/D₀) × 100%], where D_t and D₀ indicate the amount of drug released from the liposomes at certain intervals and the total amount of drug in the liposome suspension, respectively. Liposome samples were collected at the end of the study and lysed with ethanol for analysis of drug content by HPLC.