Stability evaluation of tocopheryl acetate and ascorbyl tetraisopalmitate in isolation and incorporated in cosmetic formulations using thermal analysis

Abstract

In view of the increase in the number of cosmetic preparations containing antioxidant vitamins, chiefly, due to their action in preventing the process of skin aging, there is a need to develop pre-formulation studies and to validate analytical methods in order to obtain high quality products. Thus, the objective of this research was to evaluate and compare the thermal behavior of tocopheryl acetate and ascorbyl tetraisopalmitate as raw materials, and incorporated into a base cream. Thermogravimetry (TG / DTG) and differential scanning calorimetry (DSC) were used for this purpose. Both vitamins were found to be stable up to 250ºC. The base cream (placebo) and the sample (base cream containing the vitamins) presented different weight loss. Thermal analysis has shown itself to be an excellent tool for the characterization of these vitamins and can be used in routine analysis for quality control of this type of cosmetic formulation.Uniterms: Thermal analysis. Cosmetic emulsion/qualitative analysis. Cosmetics/quality control. Tocopheryl acetate/antioxidant action. Ascorbyl tetraisopalmitate/antioxidant action. Vitamins/use in cosmetics.Considerando o potencial antioxidante das vitaminas utilizadas em produtos cosméticos, seu uso na prevenção do processo de envelhecimento da pele e a necessidade de estudos de pré-formulação que garantam o desenvolvimento de cosméticos de qualidade, foi objetivo deste trabalho avaliar e comparar o comportamento térmico dos ativos acetato de tocoferila e tetraisopalmitato de ascorbila, matérias-primas, isoladamente e incorporados em creme base. As técnicas termogravimetria/termogravimetria derivada (TG/DTG) e calorimetria exploratória diferencial (DSC) foram utilizadas para tal finalidade. Verificou-se que as vitaminas mantiveram-se estáveis até a temperatura de, aproximadamente, 250 ºC, observando-se diferença na perda de massa entre o creme base e o creme base associado às vitaminas. Assim sendo, a análise térmica mostrou-se como excelente ferramenta para caracterização das vitaminas e do creme base, podendo ser empregada em análises de rotina no controle de qualidade deste tipo de formulação cosmética.Unitermos: Análise térmica. Emulsão cosmética/análise qualitativa. Cosméticos/controle de qualidade. Acetato de tocoferila/potencial antioxidante. Tetraisopalmitato de ascorbila/ potencial antioxidante. Vitaminas/uso em cosméticos.

Ascorbyl Tetraisopalmitate Inclusion into Υ-Cyclodextrin and Mesoporous SBA-15: Preparation, Characterization and In Vitro Release Study

“…In Figure 3, the curves of the pristine gamma-cyclodextrin, the pure VC-IP, and the cyclodextrin/VC-IP complex are reported. In the DSC curve of the cyclodextrin/VC-IP complex the peak of degradation of the VC-IP was absent, while the same peak at about 350 • C is clearly visible in the curve of the pure active ingredient [18]. In fact, in the DSC curve of the complex, only the signals of the cyclodextrin were present, suggesting a good interaction between the matrix and the VC-IP [19], which probably enhances the thermal stability of the active ingredient.…”

Characteristics of vitamin E-loaded nanofibres from dextran

“…[32] Dextran showed a wide endothermic peak at 320°C followed by an exothermic peak. Due to low weight proportion of vitamin to dextran, the characteristic peak of vitamin E in thermogram of vitamin E-loaded nanofibre was weak but yet detectable while its peak started from lower temperatures which was due to its overlap with dextran peak.…”

Encapsulation of Vitamins A and E as Spray-Dried Additives for the Feed Industry

“…For VA, a first shoulder was perceived at 297 °C, and the main decomposition was found at 420 °C. The VE revealed a small shoulder at 238 °C, followed by the main stage at 366 °C [67,89]. The encapsulating agents (Figure 6b) revealed a first dehydration stage until 130 °C, followed by a one-step thermal decomposition at 308 °C for MD, 298 °C for CAP, and 325 °C for SC.…”