Desenvolvimento de nanopartículas à base de zeína e caseinato como potenciais carreadores para extrato liofilizado de Curitiba prismatica

Abstract

The advancement of research in pharmaceutical nanotechnology has driven the development of encapsulation and controlled drug release systems, aiming to optimize the therapeutic efficacy of well-established substances and enable the therapeutic use of new bioactive compounds. Among the most promising strategies are polymeric nanoparticles, capable of encapsulating a wide range of active ingredients and protecting these compounds from physicochemical degradation, thus promoting greater stability and bioavailability. Among the natural polymers used for this purpose, zein, a storage protein abundant in corn, stands out for its biocompatibility, biodegradability, and ability to form nanoparticulate matrices. To improve the colloidal stability of zein nanoparticles, stabilizing agents such as sodium caseinate are commonly added, promoting greater uniformity and control over particle size. At the same time, there is growing scientific interest in investigating native plant species with therapeutic potential, many of which are still underexplored in the literature. One example is Curitiba prismatica, a species of the Myrtaceae family, endemic to Brazil and found mainly in the states of Paraná and Santa Catarina. Studying its phytochemical and pharmacological properties may open new possibilities for the use of plant extracts in innovative formulations. In this context, the present study aimed to develop polymeric nanoparticles based on zein and sodium caseinate and evaluate their potential as carriers for the lyophilized plant extract of Curitiba prismatica. The nanoparticles were obtained through the solvent displacement precipitation method and were characterized in terms of encapsulation efficiency, average particle diameter, polydispersity index, zeta potential, and antioxidant activity. A control group (nanoparticles without extract) was included for comparative purposes. Both groups presented an average particle diameter of approximately 170 nm and a zeta potential around 322 mV, with no statistically significant differences between them. The polydispersity index (PDI) indicated better uniformity in the extract-loaded group, with a value of 0.150, compared to the control group, which showed a PDI of 0.200, suggesting that the presence of the extract contributed to a more homogeneous size distribution. An average encapsulation efficiency of 98.77% was obtained for the plant extract, demonstrating the high capacity of the system to incorporate the active compound into the nanoparticles, indicating that the process parameters were effective and that there is no immediate need for optimization in this regard. Regarding antioxidant activity, average values obtained using the DPPH IC¥ method were 37.983 mg/L, indicating low antioxidant activity of the extract-loaded nanoparticles. Given the scarcity of studies on the species Curitiba prismatica, this research contributes both to the exploration of the pharmacological potential of this native species and to the development of nano-structured systems applied to the delivery of natural compounds. Continuing the studies, with a focus on formulation optimization and detailed extract characterization, is essential to enable future therapeutic applications.