Abeer Attia Tawfik1, Jehan Alsharnoubi2, Mona Morsy3. 1. Dermatology Unit, Medical Laser Department, National Institute of Laser Enhanced Sciences Cairo University, Egypt. Electronic address: dr.abeertawfik@gmail.com. 2. Pediatrics Unit, Medical Laser Department, National Institute of Laser Enhanced Sciences Cairo University, Egypt. 3. Biology Unit, Medical Laser Department, National Institute of Laser Enhanced Sciences Cairo University, Egypt.
Abstract
BACKGROUND: Staphylococcal aureus is the most common organism which has been encountered in impetigo infection. Gold nanoparticles can be used as a tool to deliver antimicrobials or to enhance photodynamic destruction of bacteria. OBJECTIVE: To evaluate the photodynamic effect of methylene blue gold nanoparticles (MB-gold nanoparticles conjugate) on S. aureus which were isolated from impetigo lesions. PATIENT AND METHODS: Twenty children were diagnosed clinically as impetigo, and aged from 3 to 5 years of both sexes were recruited in the study. Two bacteriological samples were collected from each patient, identified and cultured. Samples of S. aureus of a concentration of 10(-1)ml were divided into four groups. S. aureus was treated by MB-gold nanoparticles conjugate, gold nanoparticles, MB, and the fourth group served as a control group. Diode laser (660 nm) was used for photoactivation. The bacterial growth inhibition was determined by two methods: the percentage of reduction of viable bacteria count and the optical density (O.D) of bacterial growth. RESULTS: The highest significant inhibitory effect on S. aureus was obtained with MB-gold nanoparticles conjugate when irradiated by diode laser 660 nm (P < 0.0001). The percentage of viable bacteria was 3%. The photoactivated gold nanoparticles showed a significant inhibitory effect on bacterial growth (P < 0.05). A non-significant inhibitory effect was elicited in other groups. CONCLUSION: The photoactivated MB-gold nanoparticles conjugate showed the maximum inhibitory effect on S. aureus activity. The gold nanoparticles proved efficacy as a drug delivery system. It enhanced the photodynamic antibacterial effect of methylene blue.
BACKGROUND: Staphylococcal aureus is the most common organism which has been encountered in impetigo infection. Gold nanoparticles can be used as a tool to deliver antimicrobials or to enhance photodynamic destruction of bacteria. OBJECTIVE: To evaluate the photodynamic effect of methylene blue gold nanoparticles (MB-gold nanoparticles conjugate) on S. aureus which were isolated from impetigo lesions. PATIENT AND METHODS: Twenty children were diagnosed clinically as impetigo, and aged from 3 to 5 years of both sexes were recruited in the study. Two bacteriological samples were collected from each patient, identified and cultured. Samples of S. aureus of a concentration of 10(-1)ml were divided into four groups. S. aureus was treated by MB-gold nanoparticles conjugate, gold nanoparticles, MB, and the fourth group served as a control group. Diode laser (660 nm) was used for photoactivation. The bacterial growth inhibition was determined by two methods: the percentage of reduction of viable bacteria count and the optical density (O.D) of bacterial growth. RESULTS: The highest significant inhibitory effect on S. aureus was obtained with MB-gold nanoparticles conjugate when irradiated by diode laser 660 nm (P < 0.0001). The percentage of viable bacteria was 3%. The photoactivated gold nanoparticles showed a significant inhibitory effect on bacterial growth (P < 0.05). A non-significant inhibitory effect was elicited in other groups. CONCLUSION: The photoactivated MB-gold nanoparticles conjugate showed the maximum inhibitory effect on S. aureus activity. The gold nanoparticles proved efficacy as a drug delivery system. It enhanced the photodynamic antibacterial effect of methylene blue.
Authors: Mariana Q Mesquita; Cristina J Dias; Maria G P M S Neves; Adelaide Almeida; M Amparo F Faustino Journal: Molecules Date: 2018-09-21 Impact factor: 4.411