PEGylated estradiol benzoate liposomes as a potential local vascular delivery system for treatment of restenosis

Abstract

This study was directed towards the preparation and optimization of PEGylated (PEG, poly(ethylene glycol)) estradiol benzoate (ESB)-loaded liposomes to be used for the treatment of restenosis by local vascular delivery. Various liposomal formulations were prepared by thin film hydration method followed by sonication. Response surface methodology was applied to study the influence of three different independent variables, on the response of entrapment efficiency (%EE). Liposomes were characterized in terms of size, zeta potential, %EE and release profile. Incorporation of ESB was higher in egg phosphatidylcholine (EPC) liposomes, whereas the drug was displaced from liposomes, as the cholesterol (Chol) content of liposome increased. The optimum formulation composed of EPC/dioleyloxy trimethylammonium propane/distearoylphosphatidylethanolamine-PEG2000 with a molar proportion of 8.5:1:0.5 had the highest EE. In vivo studies in the balloon-injured rat carotid arteries revealed the potential of ESB-loaded liposomes as efficient local and controlled drug delivery systems to reduce restenosis.

Co-delivery of Doxorubicin and PSC 833 (Valspodar) by Stealth Nanoliposomes for Efficient Overcoming of Multidrug Resistance

“…The selection of lipids for preparing liposomes to be used as a drug delivery system depends on many factors, including entrapment efficiency, as a key parameter in liposomal drug delivery, availability, cost, safety, and ease of utilization of the lipids. Encapsulation of a lipophilic drug depends, to a large degree, on the lipid composition (44,45) and occurs mainly through partitioning into the membrane (46). For DPPC and DSPC increase in the fatty acid chain length and the gel state of liposomes composed of these lipids are the factors responsible for reduced liposomal entrapment of PSC 833.…”

Nanomedicine approaches for sirolimus delivery: a review of pharmaceutical properties and preclinical studies

“…sustained-release properties, capability of hydrophobic and hydrophilic drugs entrapment, low clearance rates, surface modification, safety, cargo protection from external degradation and flexibility in adjusting physicochemical characteristics [38,40]. They also preferentially accumulate at pathologic sites of inflammation, infections and tumours [41].…”

Niosomal carriers enhance oral bioavailability of carvedilol: effects of bile salt-enriched vesicles and carrier surface charge 

“…It is obvious that increasing the concentration of bilayer-forming materials, which in turn increases the number of vesicles in a given volume, can increase the amount of drug entrapped in the vesicles. 44,45 Although enhancement of the L/D molar ratio leads to higher EE, the ratio should be chosen with care because high lipid concentrations are not appropriate for niosome preparation on an industrial scale.…”