New approaches to identification and characterization of tioconazole in raw material and in pharmaceutical dosage forms

LAMAS, MARÍA C.; ALVAREZ, VERA A.; ALVAREZ, VERA A.; CALVO, NATALIA L.; LEONARDI, DARÍO; CALVO, NATALIA L.; LEONARDI, DARÍO; LAMAS, MARÍA C.

Journal of Pharmaceutical Analysis

Elsevier

Año: 2019 vol. 9 p. 40 - 48

2095-1779

Tioconazole, a broad-spectrum antifungal agent, has significant activity against Candidaalbicans and other Candida species, and therefore, it is indicated for the topical treatment ofsuperficial mycoses. The main goal of this work is to report an exhaustive identification andcharacterization procedure to improve and facilitate the on line quality control and continuousprocess monitoring of tioconzole in bulk material and loaded in two different dosage forms:ovules and nail lacquer. The methodologies were based on thermal (differential scanningcalorimetry (DSC), melting point, and thermogravimetry(TG)), spectroscopic (ultraviolet (UV), RAMAN, near infrared (NIR), infrared spectroscopy coupled to attenuated totalreflectance (FTIR-ATR), and nuclear magnetic resonance (NMR)), microscopic and X-raydiffraction (XRD). The tioconzole bulk powder showed a high crystallinity, as observed byXRD, with a particles size distribution (3-95 μm) resolved by microscopic measurements.Tioconazole melting point (82.8 ºC) and a degradation peak centered at 297.8 °C wereobtained by DSC and DTG, respectively. An unambiguous structure elucidation oftioconazole was obtained by mono- and two- dimensional 1H and 13C NMR spectral dataanalysis. The FTIR-ATR, RAMAN and NIR spectra of both the raw material and thecommercial products were analyzed and their characteristic bands were tabulated. The bestmethods for tioconazole identification in ovules were DSC, TG, XRD, NIR and RAMAN,while NIR and FTIR-ATR were the most appropriate techniques to analyze it in the naillacquer. DSC, TG, DRX, RAMAN, FTIR-ATR and NIR spectroscopy are effectivetechniques to be used in on-line process analysis, because they do not require samplepreparation, and they are considerably sensitive to analyze complex samples.