Anais da 43ª Reunião Anual Virtual da SBQ

Selenium nanoparticles (SeNPs) have anti-cancer, antioxidant, antibacterial and anti-inflammatory action and these properties can be enhanced through association with other elements.1 The present work aimed to evaluate the antioxidant capacity (CAO) of SeNPs and hybrid Se and Cu nanoparticles (SeCuNPs), previously synthesized and characterized in different polymeric stabilizing agents. The NPs were synthesized based on the adapted literature with chitosan (QUI) and polyvinyl alcohol (PVA) as stabilizing agents.2 Once synthesized and characterized, the ABTS assay was performed to assess the antioxidant capacity of NPs. For this purpose, analytical curves were constructed with NPs and stabilizing agents. The results were expressed as a function of IC50 (concentration required to inhibit 50% of ABTS●+) and compared with Trolox (phenolic compound) and ascorbic acid (reducer) standards. Fig. 1 (a - d) represents the shape and size of the NPs obtained by transmission electron microscopy (TEM), in which there is a reduction in the size of SeCuNPs in relation to SeNPs, regardless of the stabilizing agent. However, this size variation resulting from the differentiated nucleation step in the presence of copper, was more expressive in QUI (from 94 to 36 nm). The CAO results of the synthesized NPs (Fig., 1e) showed high CAO with IC50 between 0.3 and 0.4 mg L-1 , 81-85% more efficient than the Trolox and ascorbic acid standards. The QUI and PVA stabilizers showed inhibitions lower than 10% at concentrations up to 200 mg L-1 . From the data obtained, it can be inferred that the synthesis of hybrid Se and Cu NPs promoted a reduction in size compared to SeNPs, in addition to presenting high antioxidant capacity, thus enabling applications in biological systems. Thus, further tests to assess the antioxidant capacity will be carried out to obtain complementary data on the hybrid material, for example, the ferric reducing antioxidant power (FRAP) and DPPH● radical scavenging capacity.