A vesicle is a microscopic particle composed of a lipid bilayer membrane that separates the inner aqueous compartment from the outer aqueous environment. Palmitoleate-palmitoleic acid vesicles were prepared and their physico-chemical properties were investigated. Moreover, mixed vesicles composed of palmitoleic acid and PEGylated lipid and/or a mixture of phospholipids were also prepared. The stabilizing effects of these double-chain lipids on the formation of palmitoleate-palmitoleic acid vesicles were studied. Stability of the vesicle suspension was examined using particle size and zeta potential at 30 °C. The magnitude of the zeta potential was relatively lower in the vesicle suspension with the presence of phospholipid. Although some of the mixed vesicles that were formed were not very stable, they displayed potential for encapsulating the active ingredient calcein and the encapsulation efficiencies of calcein were encouraging. The palmitoleate-palmitoleic acid-DPPE-PEG2000 vesicle showed the most promising stability and encapsulation efficiency.
Preparation of chitosan-coated fatty acid liposomes is often restricted by the solubility of chitosan under basic conditions. In this experiment, the preparation of chitosan-coated oleic acid (OA) liposomes using low molecular weight (LMW) chitosan (10 and 25 kDA) was demonstrated. These selected LMW chitosans are water soluble. The coating of the chitosan layer on OA liposomes was confirmed by its microscope images and physicochemical properties, such as zeta potential and the size of the liposomes. The "peeling off" effect on the surface of chitosan-coated OA liposomes was observed in the atomic force microscope images and showed the occurrence of the chitosan layer on the surface of OA liposomes. The size of the chitosan-coated liposomes was at least 20 nm smaller than the OA liposomes, and the increase of zeta potential with the increasing amount of LMW chitosan further confirmed the presence of the surface modification of OA liposomes.
The anti-inflammatory property of ratite oils as well as its ability to act as a penetration enhancer makes it an ideal agent to be used in transdermal formulations. The present study aims to develop an effective transfersomal delivery of 4-hydroxytamoxifen (4-OHT), an anti-cancer drug, using ratite oil as a carrier agent for the treatment of breast cancer (BC). The 4-OHT transfersomes were prepared with and without ratite oils using soy phosphatidylcholine and three different edge activators (EAs) in five different molar ratios using the rotary evaporation-ultrasonication method. Optimal transfersome formulations were selected using physical-chemical characterization and ex vivo studies. Results from physical-chemical characterization of the developed formulations found sodium taurocholate to be the most suitable EA, which recorded highest entrapment efficiency of 95.1 ± 2.70% with 85:15, (w/w) and lowest vesicle size of 82.3 ± 0.02 nm with 75:25, (w/w) molar ratios. TEM and DSC studies showed that the vesicles were readily identified and present in a nearly perfect spherical shape. In addition, formulations with emu oil had better stability than formulations with ostrich oil. Physical stability studies at 4 °C showed that ratite oil transfersomes were stable up to 4 weeks, while transfersomes without ratite oils were stable for 8 weeks. Ex vivo permeability studies using porcine skin concluded that 4-OHT transfersomal formulations with (85:15, w/w) without emu oil have the potential to be used in transdermal delivery approach to enhance permeation of 4-OHT, which may be beneficial in the treatment of BC.