Advances in fluorescent carbon dots for biomedical applications

Abstract

Carbon Dots are an emerging class of carbon-based nanoparticles, which since their discovery have attracted tremendous attention because of their exceptional fluorescent, chemical and mechanical properties as well as high photostability and biocompatibility. This unique combination of outstanding characteristics, together with the ease with which they can be synthesized, qualify carbon dots as highly promising materials for applications in electronics and biology, in particular, for biosensing, bioimaging, biotherapy and drug delivery. In this review, we present some of the most recent applications of carbon dots in biology and medicine, concentrating on their fluorescence properties, biocompatibility and efficiency; we also discuss how improvements could prompt their use in human studies. We illustrate how carbon dots, prepared through several facile and costeffective methods by either the bottom-up or the top-down route, can be used for imaging cells and bacteria and as sensing probes of metal cations. Moreover, we explain how their astonishing versatility has given rise to new biotherapy methods especially in the field of cancer theranostics.

Facile Synthesis of Surface-Modified Carbon Quantum Dots (CQDs) for Biosensing and Bioimaging

“…Quantum dots exhibit specificity to certain biologically relevant substances and have reasonably high quantum yield and broad absorption spectra [ 8 ]. On the contrary to conventional dyes, these nanomaterials are characterized with tunable, size-dependent, narrow emission spectra and long fluorescence lifetime [ 9 , 10 ]. The optoelectronic properties of the QDs come from the transformation in size-dependent energy levels systematic transformations, which are correlated with the size of quantum dots [ 8 ].…”

“…The optoelectronic properties of the QDs come from the transformation in size-dependent energy levels systematic transformations, which are correlated with the size of quantum dots [ 8 ]. Such a phenomenon is called the quantum confinement effect [ 8 , 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Quantum dots may be applied in bioimaging and biodiagnostics [ 16 , 17 , 18 , 19 ].…”

Carbon Dots as Promising Tools for Cancer Diagnosis and Therapy

“…Therefore, due to their significant nanostructures and favorable properties, over the past decade, CDs have found application in many research areas involving light such as optoelectronic [ 51 ] and medicine [ 52 , 53 ]. In particular, their interesting fluorescent properties have encouraged their wide application in several fields of life science such as sensing [ 54 , 55 ], bioimaging [ 56 , 57 ], biocatalysis [ 58 , 59 ], and therapy [ 60 , 61 , 62 ].…”

An Overview of the Recent Developments in Carbon Quantum Dots—Promising Nanomaterials for Metal Ion Detection and (Bio)Molecule Sensing

“…These factors directly influence the efficiency of the prepared materials as well as applicability in different scientific and research fields, such as electronics, environmental, and biomedical analysis. The applicability of the prepared CQDs is affected by the biocompatibility, solubility in different media, quantum yield (QY), and wavelengths of the emission and blue-and red-shifts of the absorption spectra [74,75].…”