Synthesis of C-dot by hydrothermal method and evaluation of its anti-bacterial effect against antibiotic resistant S. areus and K. pneumonea

Carbon dots (C-dots) are an emerging class of engineered nanomaterials with broad applications in medicine, bio-imaging, sensing, electronic devices, and catalysis. The study aimed to synthesize carbon nanoparticles with antibacterial therapeutic properties against clindamycin-resistant Staphylococcus aureus and ciprofloxacin-resistant Klebsiella pneumonia strains. The C-dots were prepared by a hydrothermal method. Then the synthesized carbon dot were characterized by UV-visible spectroscopy, dynamic light scattering, Fourier transform infrared spectroscopy and transmission electron microscopy. The minimum inhibitory concentration of C-dots was evaluated by the micro-broth dilution method. Antibiotic susceptibility testing was performed using the disk diffusion method. The C-dots significantly reduced S. aureus and K. pneumoniae strains growth when compared to untreated bacteria (control; P < 0.05). Therefore, the minimum inhibitory concentration (MIC) of C-dots for clindamycin-resistant S. areus and ciprofloxacin-resistant K. pneumoniae strains were 500 and 250 µg/ml, respectively. The survival percentage of S. areus and K. pneumoniae decreased to 48.05% and 11.6% respectively after treatment with 250 μg/ml C-dots. However, the viability of bacteria decreased to 3.8% and 2.5% at the concentration of 500 μg/ml.  The results show that by producing antibacterial drugs at the nanoscale, C-dots are a promising new approach to improve the effectiveness of treating infections caused by antibiotic-resistant bacterial strains.