Abstract
The emergence of antibiotic-resistant bacteria poses a critical public health
issue worldwide, which demands the development of novel therapeutic agents as viable
alternatives to antibiotics. The advent of nanoscience and technology offers the
synthesis of several potential anti-microbial agents that are effective against both
Gram-positive and Gram-negative bacterial strains. One such nanoscale material that
fascinated researchers due to its unique optoelectronic properties is Quantum Dots
(QDs). Moreover, these are found to be highly bactericidal, even against resistant
bacterial infections. Thus, a significant number of researches have been going on
globally to employ QDs as potent bactericidal agents alone or in combination with
antibiotics. Studies demonstrated that intracellular uptakes of QDs elevate the level of
reactive oxygen species (ROS) inside the cells, which turns-on cascades of intracellular
events that cause damage to DNA and proteins. However, the inherent reactive nature
of these metallic and semiconductor QDs raises huge concern for translational research
as these are found to be cytotoxic and non-biocompatible. Moreover, the human body
does not have a proper sequester mechanism to remove these metallic ions from the
body, which limits its direct applications. Recent progress in this line of interest has
focused on developing non-metallic quantum dots, such as carbon dots (CQDs) and
Black Phosphorus quantum dots (BP QDs) which showed less toxicity and
immunogenicity suitable for real-life applications. Therefore, in the present chapter, we
are going to discuss the recent development of bactericidal QDs and various types of
surface functionalization illustrated recently to increase biocompatibility.