Artemia salina leach em fotoproteção: um novo modelo para avaliar o potencial de nanopartículas para aplicação tópica

Abstract

The use of animals in research has generated heated discussions on part of society and the scientific community. This fact, associated with the need to prove the safety and efficacy of these products, has led to a growing interest in the search for an alternative method. Given this scenario, the development of new alternative methods becomes important even from an economic point of view. Therefore, this study aimed to evaluate the use of the invertebrate microcrustacean Artemia salina Leach for phototoxicity and photoprotection assays, thus evaluating the potential use of nanostructured systems for topical application against ultraviolet radiation. As a product model, solid lipid nanoparticles of the flavonoid rutin (SLNRs) were produced, which presents several activities, with emphasis on antioxidant action. SLNRs were obtained by the hot melt microemulsion technique using a high-shear homogenizer. These were characterized and evaluated for the average particle size (D50= 185±12.19 nm), polydispersity index (PDI= 0.140±0.11), zeta potential (PZ= -34.04±1.43 mV), and encapsulation efficiency (EE= 98.82±0.37%), representing satisfactory values for topical application. Regarding the physicochemical characterization, determined by thermal analysis (DTA and TG), and infrared spectroscopy by Fourier transform did not show any change in relation to the thermal profile and crystallinity of the SLNR when compared with their respective constituents. X-ray diffraction results showed a decrease in crystallinity in NLSR. The SLNR were submitted to an in vitro penetration/permeation evaluation using pig ear, where the SLNR were able to increase the penetration of rutin into the skin by up to three times when compared to free rutin at a 3.23±0.54μg/cm2 concentration and not presenting rutin permeation in the collecting liquid. The in vitro evaluation of the sun protection factor by spectrophotometry (SPFUVB) for SLNR indicated an increase greater than 6 times with SPF= 5.44±2.45. Regarding the assay with Artemia salina, the lethal doses were determined against UVA radiation (LD50=133.2±0.82 J/cm2) and UVB (LD50=0.45±0.056 J/cm2) and later performed the toxicity, phototoxicity, and photoprotection essays. SLNRs were considered non-toxic. In the phototoxicity test, the SLNR showed photochemopreventive action, mainly against UVA radiation. In photoprotection studies, formulations containing NLRS exhibited greater photoprotection against UVB radiation (86.60%±7.64 viability) than UVA (58.00%±10.95 viability). In conclusion, the method using Artemia salina L., proved to be a very effective and promising tool to evaluate the phototoxic and photoprotective potential of nanostructured systems.