Background: Fluorescence-based sensing is considered highly sensitive and fluorescent probes with improved
properties are always desired. Fluorescent carbon dots (CDs) are newly emerging quasi-spherical nanoparticles of less than
10 nm in size and belong to the carbon nano-material’s family. CDs have great potential as fluorescent probes and currently
are under open deliberation by the researchers due to their striking properties such as low environmental hazard, high
selectivity, greater sensitivity, good biocompatibility, tunable fluorescent properties and excitation dependent multicolor
Introduction: This review demonstrates various available methods for fabrication of fluorescent CDs, capping of CDs and
characterization with various techniques including UV-visible, FT-IR, and TEM. Analytical applications using CDs for the
sensing of small organic molecules, specifically nitroaromatic compounds in the environmental samples are complied.
Methods: The review covers literature related to synthesis and characterization of carbon dots. It includes around 171
research articles in this field.
Results: Carbon dots can be synthesized using numerous routes. In all cases CDs possess spectral properties with little
variation in wavelength maxima. Optical properties of CDs can be tuned by compositing these with metallic quantum dots
or by modifying their surface with desired functionalities. HR-TEM is needed to see the morphology and size of particles
whereas UV-Visible and FTIR are indispensable tools for this kind of research. These particles are successfully applied to
sense small molecules in some matrices.
Conclusion: Carbon dots are bright stars in fluorescent sensing of small molecules. However, more research is needed to
determine small organic molecules in diversified areas of analysis.