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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.
Designing of anti-acne emulsions containing herbal extracts and assessing their efficacy and unwanted effects in volunteers with mild to moderate acne
Acne is a common skin condition that affects most people, especially in adolescence. Although the precise mechanism of acne is not known, four major factors are considered to play important roles in the formation of acne: increased sebum production hyperkeratinization, overgrowth of propionibacterium acnes and inflammation. As a general strategy, anti-acne products are formulated to fight against these four factors. Since acne is a chronic skin disorder, user compliance to the prescribed anti-acne product is very important to get a response of the treatment. Unfortunately, due to the unwanted effects of anti-acne products; such as irritation, dryness, redness, user noncompliance is very common problem for the anti-acne prevention and treatment approaches. Although herbal remedies and several extracts have been used for acne since ancient times, there are limited number of scientific studies which investigated the anti-acne effects of herbal ingredients which could be effective on these four main factors associated with acne. In this study, it was aimed to develop emulsion formulations and investigate the synergistic effects of some herbal extracts incorporated in these formulations. One part of the study focused on the development, characterization and 12 weeks accelerated stability tests of emulsions while the other important part investigated the effectiveness and unwanted effects of the emulsions on volunteers with facial acne with a placebo and reference-benzoyl peroxide (BPO) 5 %-controlled, 8 weeks, double-blind clinical study. Results of the study overall showed that herbal emulsions (complex A and complex B) that were developed by incorporating herbal extract were stable enough with good rheological and sensory properties ensuring easy dispensing and application on the skin without greasiness. The clinical study results showed that, in terms of reduction of acne score and number of acne lesion, the herbal emulsions were more effective than placebo and less effective than BPO 5% and unwanted effects were less than BPO 5%, as expected. Due to a better user compliance, acne-quality of life scores of the clinical study participants were positively affected. Key words: herbal anti-acne, emulsion, stability, efficacy, Acne-QoL
Characterization studies of lipid based delivery system containing natural antioxidant
Antioxidants are well familiar in conversations or discussions that include topics such as aging and healthy skin, especially in the fields that concern cosmetics industries. Antioxidants are proven to diminish free radical concentration in the body by different types of mechanisms. Free radicals are considered the cause of many diseases and conditions and skin aging included. Antioxidants, Phenols, and flavonoids all showed great effectiveness through depleting ROS (Reactive oxidative stress) levels and scavenging free radical molecules, natural antioxidants have a tendency of being unstable, these instabilities might affect their penetration through the stratum corneum or generally total antioxidant activities. This research aimed to encapsulate natural antioxidants extracted from the fruit commonly named Indian gooseberry or latinly named Emblica officinalis from the family of Euphorbiaceae into small phospholipid nanocarriers. It's believed that liposomes will not only provide assistance for antioxidant transportation through the skin but also it will have enhanced bioavailability and stability. In the research, the final cosmetic formulation was chosen as hydrogel (Carbopol 934) due to controlled release and enhancing the stability of the liposomal formulation. Four different methods (DPPH, ABTS, FRAP, and CUPRAC) for measuring the total antioxidant amount of the extract and formulations were evaluated. The results showed that approximately 43% of total antioxidants are in 1 mg of extract. Moreover, phenols and flavonoids showed 12% of total phenols per 1 mg of extract. Design-Expert® was used to obtain the liposomal optimal formulation. Liposomes were characterized by zeta potential, particle size, and polydispersity index. All the samples' particle sizes were shown to be <108 nm and zeta potentials were shown all to be negative and the polydispersity index was presented to be less than 0.3 indicating monomodal size. The optimal formulation 13 contained 1.8% of soybean and 0.07% of cholesterol. FTIR, SEM, and rheological studies were done for further evaluation and analysis. In vitro and ex vivo comparison studies between loaded liposomes with gel formulation and Emblica officinalis extract only with gel formulation were done using Franz cell diffusion method. In vitro results showed 42.28% cumulative drug release for samples that were incorporated with liposomes which is 23.44% more than samples that were not. On the other hand, ex vivo results were considered lower but nonetheless satisfactory where samples that were incorporated with liposomes showed 21% cumulative drug release which was a 6% difference for samples that were not.