Síntese, caracterização e avaliação da estabilidade de hidroxissais lamelares de zinco intercalados com antocianinas

Abstract

The study and application of natural dyes are increasingly relevant due to the demand for sustainable and less toxic alternatives to synthetic dyes. In this work, lamellar zinc hydroxy salts (HSL) intercalated with anthocyanins extracted from the BRS Magna grape variety were synthesized and characterized, aiming to improve the stability of the compound. HSL are materials in which the interaction of the inorganic matrix (lamellae) with organic species is possible, generating properties distinct from those of the precursors and new applications for the hybrid material obtained. The process developed in this research included the preparation of a hydroalcoholic extract of anthocyanins, the synthesis of lamellar zinc hydroxy salt precursors via the coprecipitation method, followed by the intercalation of anthocyanins by anion exchange, and the subsequent characterization of the materials obtained. The formation of HSL was evaluated by X-ray diffractometry (XRD), while Fourier transform infrared spectroscopy (FTIR) was used to investigate the intercalation of the organic group. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) showed changes in the thermal stability profile of the interspersed species. From the results obtained, it was possible to use lamellar zinc hydroxy salts as matrices for the stabilization of anthocyanins, promoting the development of new materials that can be used in different areas of knowledge.