| Autor: |
Ferreira RL; Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió-AL, Brazil., Jr WM; Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió-AL, Brazil., Souza LEA; Departmento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, 04023-062 São Paulo, SP, Brazil., Navarro HMC; Setor de Genética/ICBS, Universidade Federal de Alagoas, 57072-970 Maceió, AL, Brazil., de Mello LR; Departmento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, 04023-062 São Paulo, SP, Brazil., Mastelaro VR; Instituto de Física de So Carlos, Universidade de São Paulo, 13565-905 São Carlos, SP, Brazil., Sales TO; Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió-AL, Brazil., Barbosa CDAES; Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, 57072-970 Maceió, AL, Brazil., Ribeiro AS; Instituto de Química e Biotecnologia, Universidade Federal de Alagoas, 57072-970 Maceió, AL, Brazil., da Silva ER; Departmento de Biofísica, Escola Paulista de Medicina, Universidade Federal de São Paulo, 04023-062 São Paulo, SP, Brazil., Landell MF; Setor de Genética/ICBS, Universidade Federal de Alagoas, 57072-970 Maceió, AL, Brazil., de Oliveira IN; Instituto de Física, Universidade Federal de Alagoas, 57072-970 Maceió-AL, Brazil. |
| Abstrakt: |
The emergence of drug-resistant pathogenic microorganisms has become a public health concern, with demand for strategies to suppress their proliferation in healthcare facilities. The present study investigates the physicochemical and antimicrobial properties of carbon dots (CD-MR) derived from the methyl red azo dye. The morphological and structural analyses reveal that such carbon dots present a significant fraction of graphitic nitrogen in their structures, providing a wide emission range. Based on their low cytotoxicity against mammalian cells and tunable photoluminescence, these carbon dots are applied to bioimaging in vitro living cells. The possibility of using CD-MR to generate reactive oxygen species (ROS) is also analyzed, and a high singlet oxygen quantum efficiency is verified. Moreover, the antimicrobial activity of CD-MR is analyzed against pathogenic microorganisms Staphylococcus aureus , Candida albicans , and Cryptococcus neoformans . Kirby-Bauer susceptibility tests show that carbon dots synthesized from methyl red possess antimicrobial activity upon photoexcitation at 532 nm. The growth inhibition of C. neoformans from CD-MR photosensitization is investigated. Our results show that N-doped carbon dots synthesized from methyl red efficiently generate ROS and possess a strong antimicrobial activity against healthcare-relevant pathogens. |
