THERMOGRAVIMETRIC ANALY SIS OF “VETMIKODERM” LI NIMENT FOR APPLI CATION IN TOPICAL ANTIFUNGAL THERAPY

Abstract

The liniment «Vetmicoderm», based on 4–((5–(decylthio)–4–methyl–4H–1,2,4–triazol–3–yl)–methyl) morpholin, is highly relevant due to its pronounced antimicrobial, anti-inflammatory, and regenerative effects, as confirmed by preclinical studies. This topical dosage form ensures effective treatment of dermatomycosis in animals, promoting rapid recovery, reducing therapy costs, and enhancing livestock productivity. The aim of this work is to substantiate the temperature regime of producing a topical liniment containing 4–((5– (decylthio)–4–methyl–4H–1,2,4–triazol–3–yl)–methyl)morpholin, ensuring a stable dosage form for external use with optimal pharmacotechnological and consumer properties. Methodology. Thermogravimetric analysis was performed on the liniment «Vetmicoderm» for the treatment of dermatomycosis, its emulsion base, and individual components: 4-((5-(decylthio)-4-methyl-4H-1,2,4-triazol-3-yl)methyl)morpholine, propylene glycol, olive oil, isoeumulsifier, Polawax wax, and Ercawax CE emulsifier. The analysis was conducted using a Shimadzu DTG-60 analyzer equipped with a platinum–platinorhodium thermocouple. Samples (19.06–37.42 mg) were heated from 19 to 251 °C at a rate of 10 °C/min, with α-Al₂O₃ as the reference standard. Derivatograms (T, DTA, TGA) recorded temperature changes, weight loss, and thermal effects, enabling evaluation of component thermal stability. Results and Discussion. Thermogravimetric analysis of the Liniment «Vetmicoderm» and its components shows that the active pharmaceutical ingredient 4–((5–(decylthio)–4–methyl–4H–1,2,4–triazol–3–yl)–methyl)morpholin is thermally stable up to 154 °C. Excipients (propylene glycol, olive oil, isoeumulsifier, Polawax wax, Ercawax CE emulsifier) are also stable in the 70–90 °C range, which confirms the possibility of their use in the technological process without degradation. Liniment –placebo loses 22% of weight at 85 °C due to the evaporation of moisture, while the complete formulation of «Vetmicoderm» demonstrates the gradual loss of mass: 1.9% at 43.5 °C (0.22 mg), 14% at 72.9 °C (3.07 mg), 48% at 249.7 °C (13.92 mg). This is attributed to the gradual removal of volatile components (water and propylene glycol) and the subsequent thermal degradation of excipients. The absence of significant exo- or endothermic peaks on DTA curves indicates the absence of chemical interactions between components, which ensures the stability of the formulation. The data shows the feasibility of manufacturing the liniment at 70-90 °C in a closed system (sealed conditions) to guarantee the preservation of its pharmacotechnological properties. Conclusions. Thermogravimetric analysis has established that the manufacturing process of the liniment «Vetmicoderm» should be conducted at 70–90 °C in sealed equipment. The TGA results confirm that the formulation components do not interact with each other, thereby ensuring the stability of the liniment as a mixture. Based on the thermogravimetric analysis and a comprehensive evaluation of the thermal stability of the «Vetmicoderm» liniment components, further studies may focus on expanding the scientific and practical aspects of drug development and its introduction into production.