p,p'-Methoxyl-diphenyl diselenideincorporation into polymeric nanocapsules improves its antinociceptive action: Physicochemical and behavioral studies.

The p,p'-methoxyl-diphenyl diselenide [(OMePhSe)2] is an, organoselenium compound that elicits antinociceptive action in different, animal models of pain. However, the compound has physicochemical, Limitations that delay its clinical studies. Herein, (OMePhSe)2, nanocapsules were developed and their physicochemical properties were, analyzed using different techniques (Scanning electron microscopy with, field emissionguns, wide-angle X-ray diffractometry, fourier-transform, infrared spectroscopy, thermogravimetric analysis and differential, scanning calorimetry). The antinociceptive action of (OMePhSe)2 free or, nanoencapsulated was evaluated in an animal model of thermal nociception., The (OMePhSe)2 nanocapsules or the free compound (25mg/kg, 10ml/kg), were administered to Swiss mice by the intragastric (i.g.), intraperitoneal (i.p.) or subcutaneous (s.c.) route in a single or, repeated administration regimen. The (OMePhSe)2 nanocapsules had, spherical shape, no chemical interaction among the formulation components, and high thermal stability. Treatment with (OMePhSe)2 elicited an, antinociceptive action independent of the administration route and, regimen schedule. The (OMePhSe)2 incorporation into nanocapsules, prolonged and improved the compound antinociceptive action. The, (OMePhSe)2 antinociceptive action was influenced by the route of, administration (intragastric>intraperitoneal>subcutaneous) and by the, vehicle used (NCs>canola oil). Altogether, the current study, demonstrated that the (OMePhSe)2 nanoencapsulation increased the compound, thermal stability and the antinociceptive action in mice, suggesting that, the polymeric nanocapsules provided advantages in comparison to the free, compound form.