RESUMEN
Basal cell carcinoma (BCC) is one of the commonest malignancies occurred on sun-exposed skin, mainly by UV-B radiation, of lighter-skinned individuals. The aim of the present study was to develop advanced drug delivery formulations used in BCC therapy that overcomes chemotherapy-induced side-effects of skin photosensitivity by an integrative approach of nanoencapsulation in conjunction with combination therapy that uses chemotherapeutic, chemoprotective and sunscreen agents. The combination of anticancer drug together with sunscreen agent is very useful in therapy, especially for individuals who are more exposed to the sun without using a sunscreen. Nanostructured lipid carriers (NLCs) employed as drug delivery systems were co-loaded with 5-fluorouracil (5-FU), a hydrophilic chemotherapeutic drug, and ethylhexyl salicylate (EHS), a lipophilic UV-B sunscreen agent. The NLCs were developed using bioactive squalene (50.8% w/w) from amaranth seed oil as chemoprotective agent. By varying the concentrations of 5-FU and EHS, the co-loaded NLCs presented particle sizes of about 100nm, acceptable physical stability with values smaller than -25mV and appropriate entrapment efficiency that reaches values over 65% for both types of drugs. The UV-B blocking ability of EHS loaded into NLCs were influenced by the concentration of 5-FU. The amaranth oil offered a capacity of 70% in scavenging the free radicals. In vitro drug release showed that NLCs presented sustained release of 5-FU that followed the Fick's law of diffusion.