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.
['Ferreira-Nunes|Ricardo|R|', 'Ferreira|Larissa A|LA|', 'Gratieri|Tais|T|', 'Cunha-Filho|Marcilio|M|', 'Gelfuso|Guilherme M|GM|https://orcid.org/0000-0002-1924-7885']
D000818:Animals D002192:Canrenone D003879:Dermatologic Agents D004355:Drug Stability D005079:Excipients D007478:Iontophoresis D057230:Limit of Detection D016014:Linear Models D053758:Nanoparticles D015203:Reproducibility of Results D012867:Skin D012869:Skin Absorption D013148:Spironolactone D013552:Swine
spironolactone canrenone skin permeation iontophoresis bioanalytical method electrolysis