A rapid method for total Β-escin analysis in dry, hydroalcoholic and hydroglycolic extracts of Aesculus hippocastanum L. by capillary zone electrophoresis.

INTRODUCTION: Seeds of Aesculus hippocastanum L. are used in European phytotherapy to treat inflammatory and vascular problems, and also to help in the regulation of the microcirculation. Thus, the quality control of herbal medicines using this species is important. OBJECTIVE: To develop and to optimise a capillary zone electrophoresis method to determine total ß-escin in different extracts of A. hippocastanum L. METHODS: The optimal condition found through chemometric approach was: 25 mmol/L of bicarbonate-carbonate buffer, pH 10.3; +20 kV of voltage; 20°C of cartridge temperature; direct ultraviolet detection at 226 nm; 13 mbar injection for 5 s and analysis time within 6 min. RESULTS: Repeatability, coefficient of variation (CV; %) = 3.19, 3.07 and 1.89 (n = 12), and intermediate precision, CV (%) = 3.05, 3.53 and 2.99 (n = 24) for dry, hydroalcoholic and hydroglycolic extracts, respectively were achieved. The accuracy was evaluated through recovery tests in concentration levels of 100, 150 and 200 g/L, ranging from 98.17 to 104.68%. The proposed method exhibited linearity (r = 0.9983) in the concentration range from 101.4 to 907.2 g/L and limits of detection and quantification equal to 11.63 and 38.76 g/L respectively. CONCLUSION: A fast and reliable methodology for determination of total ß-escin was successfully validated and applied on extracts of A. hippocastanum L. demonstrating its usefulness to quality control of medicines containing this plant species.

Permeation profiles of resveratrol cream delivered through porcine vaginal mucosa: Evaluation of different HPLC stationary phases.

Trans-resveratrol affects biological systems in a multitude of ways, but its oral bioavailability is remarkably poor due to in vivo metabolization. This drawback has fomented the development of new strategies for systemic delivery, such as transmucosal delivery via the vaginal route, which is our main focus here. In this sense, our pioneering study purposed to evaluate the trans-resveratrol permeation efficacy through this route. For that, we used a previously validated method and tested it with three different stationary phases: a commercial C18 column and two laboratory-made chromatographic columns containing poly(methyloctadecylsiloxane) (PMODS) thermally immobilized onto zirconized silica (Zr-PMODS) or titanized silica (Ti-PMODS). The permeation experiments showed that resveratrol, in the formulation used, was not successfully delivered to the bloodstream - it was actually retained within the vaginal mucosa, which suggests a local use rather a systemic one.

Studies with emulsion containing trans-resveratrol: in vitro release profile and ex vivo human skin permeation.

Resveratrol is a phenolic compound that has been widely studied in the last years because of its extensive pharmacological properties. It also has physicochemical properties that are adequate for diffusion through the human skin. An analytical method by high performance liquid chromatography was developed and validated for its determination in transdermal emulsion, as well in receptor media and skin layers. The trans-resveratrol release kinetic followed the Higushi's model (R(2) = 0.9926) with steady-state diffusion flux and lag time of 138.5 µg cm(-2) h(-1) and 0.49 h, respectively. It showed a percentage at 64.96 % for permeation. Thus, the results suggest that the emulsion studied is a potential vehicle for transresveratrol administration by transdermal route.