Evaluation of Antibacterial Properties of Carbon Quantum Dots on Streptococcus mutans—In Vitro Study

Abstract Background: Carbon quantum dots (CQDs), also known as carbon dots, are extremely small (less than 10 nm), luminous carbon nanoparticles with some sort of surface passivation. These dots have a variety of qualities, including low cytotoxicity, antibacterial action mostly by bacterial cell wall destruction, no environmental risk, and an inexpensive price. in addition to different simple synthetic routes. Objectives: Testing the sensitivity of different concentrations of CQDs on oral Streptococcus mutans using agar well technique then comparing with 0.2% chlorhexidine and deionized water, to assess the antibacterial properties of CQDs. Materials and Methods: Agar well technique was used. No bacterial growth was measured when inhibition zones around each well were seen. No inhibition zone means a full resistance of the bacteria to the tested agent. Results: The results revealed that all the tested concentrations of CQDs exhibited good antibacterial activity against S. mutans with different inhibition zones when comparing them with chlorohexidine. Conclusion: Even low concentrations of CQDs have good antibacterial activity against S. mutans , with an easy method of synthesis and affordable price, and this could be a new effective material to be used in dentistry and in antibacterial application.