RESUMO
In this work, a novel antibacterial nanocomposite system was developed using mesoporous silica (MSN) as an effective nanocarrier, and the resultant nanocomposites demonstrated remarkable antibacterial performance due to the synergistic effect among nano zinc oxides, silver nanoparticles, and polydopamine (PDA). The successful synthesis of MSN/ZnO@PDA/Ag nanocomposites was confirmed. The physicochemical properties and the morphologies of these nanocomposites were investigated. It was found that the particle size increased along with the evolution of these nanocomposites. Besides, nano zinc oxides were formed in the nanochannels of mesoporous silica with a particle size about 2 nm, and that of silver nanoparticle was less than 50 nm. In addition, the results revealed that the presence of mesoporous silica could effectively prevent the formation of large-size silver nanoparticles and facilitate their well dispersion. Due to the synergistic effect among nano zinc oxides, silver nanoparticles, and polydopamine, these nanocomposites exhibited remarkable antibacterial performance even at a low concentration of 313 ppm, and the antibacterial mechanism was also elucidated. Therefore, this work provides a facile and controllable approach to preparing synergistically antibacterial nanocomposites, and the remarkable antibacterial performance make them suitable for practical applications.
Assuntos
Antibacterianos , Indóis , Nanocompostos/química , Polímeros , Prata , Óxido de Zinco , Antibacterianos/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Indóis/química , Indóis/farmacologia , Nanopartículas Metálicas/química , Polímeros/química , Polímeros/farmacologia , Dióxido de Silício/química , Prata/química , Prata/farmacologia , Óxido de Zinco/química , Óxido de Zinco/farmacologiaRESUMO
Tea tree oil, a natural antibacterial compound, cannot be used effectively because of its volatile nature. In this work, a biocompatible carrier was prepared and loaded with tea tree essential oil. The carrier was prepared via the electrostatic or chemical action of aminated mesoporous silica and sodium rosin for achieving a low volatilization rate of tea tree essential oil. A synergistic antibacterial effect was observed between sodium rosin and tea tree essential oil. This method utilized the positive charge of the amino group and the condensation reaction with the carboxyl group to achieve physical and chemical interactions with sodium rosin. Fourier Transform Infrared, Brunauer-Emmet-Teller, Zeta potential, SEM, TEM, and TG were performed to characterize the structure and properties of the samples. Compared to the electrostatic effect, the chemically modified system exhibited a longer sustained release, and the sustained release curve followed the Korsmeyer-Peppas release model. Also, the antibacterial properties of the chemically modified system exhibited better minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) respectively, the MIC and MBC forE. coliwere 0.3 mg ml-1and 0.6 mg ml-1respectively, forS. aureuswere 0.15 mg ml-1and 0.3 mg ml-1respectively. More strikingly, the sample also demonstrated long-term antibacterial performance. Therefore, this work provides a new way for the delivery of volatile antibacterial drugs to achieve sustained-release and long-lasting antibacterial effects.
Assuntos
Antibacterianos/química , Resinas Vegetais/química , Dióxido de Silício/química , Óleo de Melaleuca/química , Antibacterianos/farmacologia , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Sinergismo Farmacológico , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Porosidade , Resinas Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Staphylococcus aureus/efeitos dos fármacos , Óleo de Melaleuca/farmacologiaRESUMO
Silanized iminodiacetic acid (GLYMO-IDA) modified mesoporous silica (G-SBA) was prepared following a co-condensation method. G-SBA/Cu2+, G-SBA/Zn2+ and G-SBA/Cu2+-Zn2+ were obtained through the impregnation method with coordination by GLYMO-IDA. SBA/CuO, SBA/ZnO, and SBA/CuZnO were generated after calcination of G-SBA/Cu2+, G-SBA/Zn2+ and G-SBA/Cu2+-Zn2+. After modification, the amount of metal ion was 6 to 70 times higher than that of the blank mesoporous silica. The diameter of nano-copper oxide particles in mesoporous silica was 4.8 nm. The bacteriostatic rates of SBA/CuO at a copper oxide concentration of 250 ppm against E. coli and S. aureus were 85.87% and 100%, respectively. SBA/CuO and SBA/CuZnO with {111} lattice planes exhibited better antibacterial effects compared to the commercial-grade nano-zinc oxide and nano-copper oxide. When exposed to ultraviolet light, SBA/CuZnO displayed the highest photocatalytic activity and optimal antimicrobial effect. Therefore, SBA/CuZnO can be an alternative to antibiotics because of its non-toxic nature and good antibacterial properties.