Prescription, preparation process optimization and quality evaluation of myocardium-targeting liposomes of panax notoginseng saponins

Objective:To optimize the prescription and preparation process of myocardium-targeting liposomes of panax notoginseng saponins and evaluate its quality.Methods:The common liposomes of panax notoginseng saponins(L-PNS)were prepared by thin-film dispersion plus ultrasonic method.Single-factor experiment and response surface design methodology were carried out to optimize the prescription of L-PNS.Then L-PNS modified by esmolol analogue(PAC-L-PNS) was prepared according to the optimal prescription, and its characterization, storage stability and characteristics of drug release in vitro were studied.Results:The optimal prescription and preparation of L-PNS were as follows:the mass ratio of phospholipid to cholesterol was 9:1, the ratio of drug to phospholipid was 1:20, the ultrasonic power was 63 W, the ultrasonic time was 10 min, the hydration time was 15min, and the concentration of drug was 1mg/mL.The particle size of PAC-L-PNS on the basis of optimal prescription was(222.70±2.55)nm, the Zeta potential was(+32.73±0.25)mV, and the entrapment efficiency and drug loading were 64.62%and 11.52%, respectively.The results of stability test showed that the leakage rates of L-PNS and PAC-L-PNS were both lower 30%within 48 hours, and there was no burst release phenomenon, indicating good stability; the in vitro release results showed that the cumulative release rates of L-PNS and PAC-LPNS in 72 h were 35.88%and 32.86%, respectively.Both of them were released smoothly without obvious burst release behavior and had a slow and controlled release effect.Conclusion:Based on the optimal prescription and preparation process, the PAC-L-PNS obtained by thin-film dispersion plus ultrasonic method has uniform particle distribution, positive surface charge, good dark-storage stability and slow release in vitro.