The continuous emergence of resistant Mycobacterium tuberculosis keeps tuberculosis (TB) treatment options still insufficient, and new therapeutic alternatives are urgently needed. Considering the antimycobacterial activity of phenazine derivatives previously reported by our research group, we aimed to explore possible applications to circumvent the resistance in M. tuberculosis. Firstly, we evaluated the antimicrobial activity of seven benzo[a]phenazine derivatives against eleven M. tuberculosis strains: ten resistant and one susceptible (H37Rv). Then, we determined the cytotoxicity of benzo[a]phenazine derivatives and investigated the possible mechanism of action of the most promising compound. Among them, compound 10 was the only one active against all strains evaluated, with a minimum inhibitory concentration between 18.3 and 146.5 µM. For some resistant strains, this compound showed antimicrobial activity higher than rifampicin and it was also active against MDR strains, indicating an absence of cross‐resistance with anti‐TB drugs. Also, 10 showed a pharmacological safety for further in vivo studies and its mechanism of action seems to be related to oxidative stress. Thus, our findings indicate that benzo[a]phenazine derivatives are promising scaffolds for the development of new anti‐TB drugs, mainly focusing on the treatment of resistant TB cases.
The use of surface-functionalised polymers has shown great potential for application, emphasising the development of flexible optoelectronic devices (FOD). There are several ways to carry out this functionalisation, attributing different characteristics to the resulting material. In the present study, polyethylene terephthalate (PET) films were surface functionalised with [4-(2-hydroxy naphthyl)diazenyl] benzoic acid using UV radiation and direct grafting method. The resulting films were characterised using different techniques, which enabled the identification of functional groups characteristic of the compound azo, thus proving that both methods used for surface functionalisation were efficient. Subsequently, the sensing capabilities of these films was evaluated by being exposed to solutions of different cations. The fluorescence signal was the measurable response, in which its variation is dependent on the interaction of analytes with the functionalised surface of the PET film. The main advantages observed in this study are simplicity, low cost and the possibility of using recycled polymer, contributing to sustainable development and environmental conservation.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.