Caracterização de micro e nanopartículas de drogas vegetais medicinais por meio de diferentes técnicas analíticas

Abstract

Natural products have, in recent decades, taken on an important role in society for the treatment of diseases, stemming from traditional customs and popular wisdom. The guarantee of the efficacy and safety of their treatments depends on several factors, including good physicochemical properties, and must comply with current legislation. This study aimed to characterize micro and nanoparticles of Myracrodruon urundeuva, Sideroxylon obtusifolium, and Ziziphus joazeiro using different analytical techniques, in order to obtain data that seek to qualify and specify these plant-based drugs. Their thermogravimetric profiles were determined through Thermogravimetry (TG) using the tangent method and Differential Thermal Analysis (DTA) by measuring their combustion enthalpies corresponding to the main degradation stages. For microparticle analysis, size, number, and volume ranges were obtained between ≤ 6.25µm and ≥ 150 µm, as well as their morphological aspects such as Circularity, Convexity, and Elongation, using Morphologi G3SE. The quantification of nanoparticles was made possible through prior aqueous dispersion and filtration of the plant drugs, followed by nanoparticle tracking analysis using NTA, Nanosight NS-300. The results revealed distinct thermal profiles among the different populations of the three species of plant drugs, attributed to the nature of the plant matrix and particle size. The morphological aspects indicated a higher number of particles ≤ 6.25µm and a greater volume of particles ≥ 150 µm in almost all populations of plant drugs, along with a higher number of circular particles in Quixabeira and Juazeiro, and fewer elongated particles in Aroeira. The correlation between the energy levels of the exothermic DTA peak and the volume of particles ≥ 150 µm in morphology was directly proportional in certain populations of Aroeira and Quixabeira. The nanoparticle quantification method produced polymodal curves, with sizes ranging between 10- 760nm for most of the drugs, with S. obtusifolium being richer in nanoparticles. This study achieved its proposed objectives in the thermal characterization using TG and DTA, enabling the distinction of plant-based drugs. Their morphological profile, analyzed through Morphologi G3SE, allowed the evaluation of the technology used in obtaining the drugs based on the quality of the microparticles, and the quantitative determination of nanoparticles in medicinal plant-based drugs was possible using the Nanosight NS-300, highlighting the need to improve extraction processes for size standardization. These technologies prove to be quite promising for the characterization and quality control of medicinal plant-based drugs.