Development of liposomal carrier systems of hydrolyzed collagen, resveratrol, retinol and investigation of their penetrations

In recent years, not only for cosmetic products but also for the administration of drugs, transdermal delivery is becoming an important route of administration. Percutaneous permeation of molecules is controlled by the diffusion laws and is a big challenge in biomedical sciences. Transdermal delivery systems have many advantages such as avoidance of the first-pass metabolism, sustained-release opportunity and less frequent dosing, ease of application, and better user compliance. Ethosome is one of these new and promising delivery systems which is a new generation of liposome and because of the presence of alcohol in its structure, it offers an increased solubility for hydrophilic, hydrophobic and amphiphilic active materials. Also, the smaller and more flexible structure makes ethosome a better carrier than liposome. Resveratrol, retinol and hydrolyzed collagen ethosomes were prepared as a possibility of developing new delivery systems with these anti-aging ingredients. The results of the studies showed that the ethosomes were easy to produce and stable at the duration of the tests (180 days at 25ºC±2ºC), no phase separation or bottom precipitation was observed; the changes in the measurements of particle size, size distribution, poly-dispersity index, zeta potential, pH, density, and conductivity were within acceptable intervals. The presence of alcohol increased the solubility of the ingredients resulting in good entrapment of respective active materials in ethosomes at a minimum of 86 % and retained the entrapped actives at a minimum of 71% level after 180 days. In-vitro release studies by Franzcell diffusion system were performed with the ethosome formulations using two different synthetic membranes; Strat-M® (layered skin mimicking) and 12-14KD cellulose acetate dialysis membrane. The release rates of the actives from ethosomes were compared with the simple solutions of the actives at 1,5%. The results clearly showed that ethosomes released the actives in a sustained release manner and the release rates were slower when Strat-M® was used.