Carbon Quantum Dots: A Potential Candidate for Diagnostic and Therapeutic Application

Abstract

Among various quantum dots, carbon quantum dots (CQDs) are getting much more attention due to their nontoxicity and high water solubility. CQDs with or without functionalization/passivation possess different fluorescent properties. Moreover, simple and economical procedure involved in their preparation makes them a reliable substitute for nano-materials/semiconductor quantum dots. Due to their tunable fluorescent properties, these carbon quantum dots find application in anticancer studies, tissue engineering, nano-medicine and targeted drug delivery, electrochemical sensing, bio-sensing, and bio-imaging. Also, these CQDs are capable of showing high conductivity and therefore can be useful for improving the electrical/conductive nature of different materials. The CQDs can find significant role in LEDs. CQDS can be prepared by top-down approaches or bottom-down approaches. Top-down approaches involve arc discharge method, laser ablation, electrochemical oxidation, and chemical oxidation, and the bottom-down approaches include combustion, pyrolysis, microwave-assisted method, ultrasonic method, oxidative acid treatment, and hydrothermal methods. In this chapter we have tried to give an insight to the preparation and biological applications of CQDs.