3 research outputs found
Reactive nitrogen/oxygen species production by nitro/nitrosyl supramolecular ruthenium porphyrin complexes.
This manuscript reports on new nitro/nitrosyl Ru-based complexes, which were synthesized with the
purpose of using them as precursors to obtain supramolecular ruthenium porphyrin species ({TPyP[Ru
(NO2)(5,50-Mebipy)2]4}(PF6)4) and ({TPyP[Ru(NO)(5,50-Mebipy)2]4}(PF6)12). The photochemical and
photophysical properties of these porphyrin species were investigated. Results show that the complex
containing nitrite is able to produce NO by homolytic O?NO cleavage (FPPh
NO = 0.05) while the {TPyP[Ru
(NO)(5,50-Mebipy)2]4}(PF6)12 does it by direct labilization (FPPh
NO = 0.53) of the Ru NO bond.
Furthermore, a triplet quantum yield of 0.09 and 0.27 was observed for complexes containing nitrite
and nitric oxide, respectively. The reactive oxygen species quantum yield for the complex {TPyP[Ru(NO)
(5,50-Mebipy)2]4}(PF6)12 (0.78) is consistent with the sum of quantum yields NO release (0.53) and triplet
state (0.27), which suggests that both processes participate in the formation of the reactive species. Our
results show that combining these characteristics, NO production and triplet states, on the same platform
could induce a synergic effect, leading to a considerable improvement in the photodynamic action of
these complexes
Hancornia speciosa latex for biomedical applications: physical and chemical properties, biocompatibility assessment and angiogenic activity
The latex obtained from Hancornia speciosa is used in folk medicine for treatment of several diseases, such as acne, warts, diabetes, gastritis and inflammation. In this work, we describe the biocompatibility assessment and angiogenic properties of H. speciosa latex and its potential application in medicine. The physical-chemical characterization was carried out following different methodologies (CHN elemental analyses; thermogravimetric analyses and Fourier transform infrared spectroscopy). The biocompatibility was evaluated through cytotoxicity and genotoxicity tests in fibroblast mouse cells and the angiogenic properties were evaluated using the chick chorioallantoic membrane (CAM) assay model. The physical-chemical results showed that the structure of Hancornia speciosa latex biomembrane is very similar to that of Hevea brasiliensis (commercially available product). Moreover, the cytotoxicity and genotoxicity assays showed that H. speciosa latex is biocompatible with life systems and can be a good biomaterial for medical applications. The CAM test showed the efficient ability of H. speciosa latex in neovascularization of tissues. The histological analysis was in accordance with the results obtained in the CAM assay. Our data indicate that the latex obtained from H. speciosa and eluted in water showed significant angiogenic activity without any cytotoxic or genotoxic effects on life systems. The same did not occur with H. speciosa latex stabilized with ammonia. Addition of ammonia does not have significant effects on the structure of biomembranes, but showed a smaller cell survival and a significant genotoxicity effect. This study contributes to the understanding of the potentialities of H. speciosa latex as a source of new phytomedicines.Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP