Oxaliplatin preformulation studies for the development of innovative topical drug delivery systems

Journal of Thermal Analysis and Calorimetry - The objectives of this study were to verify the viability of the photoinitiating system using curcumin as a photoinitiator and glycerol as a...     

Thermal analysis used to guide the production of thymol and Lippia origanoides essential oil inclusion complexes with cyclodextrin

This study aimed to use thermal analysis and other analytical tools to guide the production of thymol (TML) and essential oil of Lippia origanoides (EO) solid inclusion complexes from a screening of different cyclodextrins (CDs) types and production methods (freeze drying, spray drying, rotary evaporation and supercritical CO₂). According to the phase solubility diagrams, the best complexation efficiency of TML was achieved using hydroxypropyl-β-cyclodextrin (~ 0.7), comparing to the natives CDs, which showed values below 0.5. Thermogravimetry was effective in evaluating the amount of drug inclusion complexes in each solid sample by measuring the evaporation of TML, which was dependent of its degree of interaction with the CD. Freeze drying was the most effective method in originating true inclusion complexes in solid state producing the encapsulation of nearly 70% of available TML which were stable at temperature ranges from 200 to 280 °C. Indeed, according to the stability assay, the shelf-life increase achieved for the TML standard was 354%, while the EO had a stability increase of around 45%. Finally, the antifungal effect against Candida albicans (ATCC 14053) was increased in complexed forms in about 1.5 times and 5.4 times for EO and TML, respectively, while the antifungal activity for Trichophyton mentagrophytes (ATCC 11481) was increased with TML and EO encapsulated with CD in more than 22 times and 45 times, respectively, compared to their free forms. Thus, the optimized inclusion complexes seem to be promising in pharmaceutical field for a future development of topical preparations containing TML and its natural substrates.

     

Stability‐indicating analytical method of quantifying spironolactone and canrenone in dermatological formulations and iontophoretic skin permeation experiments

A simple, stability‐indicating, chromatographic method of quantifying spironolactone (SPI) and its metabolite, canrenone (CAN), in the presence of excipients typical in dermatological formulations and skin matrices in studies of passive and iontophoretic permeation was proposed and validated here. SPI and CAN were separated using a reversed‐phase column with a mobile phase of methanol–water (60:40, v/v) at a flow rate of 1.0 mL/min. Data were collected with a UV detector at 238 and 280 nm, with retention times of 6.2 and 7.9 min for SPI and CAN, respectively. The method was precise, accurate and linear (r² > 0.99) in a concentration range of 1–30 μg/mL, and recovery rates of SPI and CAN from the different skin layers exceeded 85%. The method was not only sensitive (LOD of 0.05 and 0.375 μg/mL and LOQ of 0.157 and 1.139 μg/mL for SPI and CAN, respectively) but also selective against skin matrices and highly representative components of topical formulations. The method moreover demonstrated SPI's degradation in iontophoresis by applying Pt–AgCl electrodes and its continued drug stability using Ag–AgCl electrodes. Altogether, the method proved valuable for quantifying SPI and CAN and may be applied in developing and controlling the quality of dermatological products.     

Evolution of quality on pharmaceutical design: regulatory requirement?

Accreditation and Quality Assurance - Quality by design (QbD) concept was first outlined by quality pioneer Joseph M. Juran, who believed quality could be designed into a product, preventing,...