Preparation and evaluation of anti-wrinkle cream containing saffron extract and avocado oil.

BACKGROUND: Recently, many compounds or extracts from natural sources are used for reducing facial aging and wrinkles. OBJECTIVE: This study investigates the preparation and evaluation of the safety and efficacy of saffron extract and avocado oil used for anti-wrinkle topical cream. METHODS AND MATERIALS: Oil in water cream was prepared containing avocado oil and the saffron extract. Accelerated stability tests were carried out due to 6 months accordingly through the International Council for Harmonization (ICH) guideline. For clinical studies, topical cream was applied by twenty healthy volunteers daily, for 12 weeks. Improvement in wrinkle grading by a Global Aesthetic Improvement Scale (GIAS), depth and volume of the nasolabial fold, thickness, and density of dermis, and determination of the skin biophysical parameters were evaluated at the baseline, 6th and 12th week. RESULT: During the period of storage, the formulation showed no variation in physicochemical properties. The clinical evaluation showed at least one-grade improvement in GIAS in 30% and 45% of participants, after 6 and 12 weeks, respectively. Subjects were "moderately satisfied" with the treatment. In addition, the area and volume of nasolabial folds were significantly reduced. Moreover, net elasticity (R5) and gross elasticity (R2) showed a significant increase after 12 weeks of treatment. There was no report of allergic reactions, and no changes in skin hydration occurred during the treatment. CONCLUSION: The results of this study showed that saffron extract and avocado oil anti-wrinkle topical cream is an efficient and safe treatment for facial skin rejuvenation.

Gliclazide microcrystals prepared by two methods of in situ micronization: pharmacokinetic studies in diabetic and normal rats.

The low water-solubility of gliclazide (GL) leads to a low dissolution rate and variable bioavailability. The aim of this study was to investigate the effect of micronization on the absorption and pharmacokinetics of GL after oral administration in rats. GL microcrystals were prepared using solvent-change and pH-shift methods. Scanning electron microscopy showed considerable changes in the shape and size of crystals using both methods. In the optimized formulation of each method, the particle size of treated GL was reduced about 30 (from 290 to 9.9 microm) and 61 times (to 4.76 microm) by solvent-change and pH-shift methods, respectively. Recrystallized samples showed faster dissolution rate than untreated GL particles. Glucose-lowering effect, C(max), and area under the drug concentration-time profile (area under the curve (AUC)) were compared in diabetic and normal rats. AUC and C(max) were increased by microcrystals in both groups of animals. Administration of 40 mg/kg of GL in the form of untreated drug and microcrystals obtained by solvent-change and pH-shift methods caused 12.49% and 21.04% enhancement in glucose-lowering effect of GL in diabetic rats, respectively.

Dissolution enhancement of gliclazide using pH change approach in presence of twelve stabilizers with various physico-chemical properties.

PURPOSE: The micronization using milling process to enhance dissolution rate is extremely inefficient due to a high energy input, and disruptions in the crystal lattice which can cause physical or chemical instability. Therefore, the aim of the present study is to use in situ micronization process through pH change method to produce micron-size gliclazide particles for fast dissolution hence better bioavailability. METHODS: Gliclazide was recrystallized in presence of 12 different stabilizers and the effects of each stabilizer on micromeritic behaviors, morphology of microcrystals, dissolution rate and solid state of recrystallized drug particles were investigated. RESULTS: The results showed that recrystallized samples showed faster dissolution rate than untreated gliclazide particles and the fastest dissolution rate was observed for the samples recrystallized in presence of PEG 1500. Some of the recrystallized drug samples in presence of stabilizers dissolved 100% within the first 5 min showing at least 10 times greater dissolution rate than the dissolution rate of untreated gliclazide powders. Micromeritic studies showed that in situ micronization technique via pH change method is able to produce smaller particle size with a high surface area. The results also showed that the type of stabilizer had significant impact on morphology of recrystallized drug particles. The untreated gliclazide is rod or rectangular shape, whereas the crystals produced in presence of stabilizers, depending on the type of stabilizer, were very fine particles with irregular, cubic, rectangular, granular and spherical/modular shape. The results showed that crystallization of gliclazide in presence of stabilizers reduced the crystallinity of the samples as confirmed by XRPD and DSC results. CONCLUSION: In situ micronization of gliclazide through pH change method can successfully be used to produce micron-sized drug particles to enhance dissolution rate.

An investigation on the solid dispersions of chlordiazepoxide.

The aim of this study was to prepare solid dispersions of chlordiazepoxide techniques to improve its dissolution rate. To this end, three techniques namely, two solvent methods and co-grinding technique were used. Solid dispersions of chlordiazepoxide in polyvinylpyrrolidone (PVP), Eudragit E100, Mannitol and Sorbitol with two different ratios of drug to carrier (5:5 and 1:9) were prepared. These solid dispersions were evaluated using dissolution tester to monitor dissolution behaviour and Fourier-transform infrared spectroscopy to investigate interaction between the drug and carriers in solid dispersion samples. Solid dispersion of chlordiazepoxide with all three carriers (PVP, mannitol and eudragit E) prepared by solvent method showed considerable increase in the dissolution rate of chlordiazepoxide in comparison with physical mixture and pure drug at different pH values. According to the results of this investigation cogrinding technique yields solid dispersions with a less improved dissolution rate than does the solvent deposition technique. Infrared studies showed no interaction between chlordiazepoxide and carriers in solid dispersions in solid state.