Recent developments in carbon dots as smartphone-based fluorescent sensors: A bibliometric study

Carbon dots (CDs) are form of carbon-based nanoparticles that have different merits such as high photostability, tunable fluorescence characteristics, biocompatibility, and easy synthesis from various carbon precursors. Due to their sensitive and selective nature towards different types of analytes, CDs have drawn considerable interest over the years in the field of sensing. The presence of different analytes like heavy metal ions, pesticides, antibiotics, anions, dye molecules and nitro compounds in water system are raising concern for the environmental and healthcare safety. Hence, it is crucial to build fast, sensitive as well as selective point of care (POC) testing techniques for the analytes. CDs have emerged as a viable fluorescent material for smartphone-based sensors for POC diagnostics and immediate tracking of different analytes. CDs and smartphone technology can be combined to create sensing platforms that are portable, affordable, and easy to use in a variety of circumstances. In this review, different synthetic approaches, functionalization, optical properties and applications of CDs-based smartphone fluorescent sensors for the detection of different analytes are highlighted. Further, the different types of sensing mechanisms are also discussed. Along with that a bibliometric study is provided in order to map the intellectual structure, research evolution, and new hotspots in the subject of CDs as a smartphone based fluorescent sensor. With an emphasis on the potential of CDs-based fluorescent sensors to transform POC diagnostics and to promote sustainable developments, the potential challenges and future prospects of this developing sectors are also covered.