Fig. 3From: A Brief Review of Carbon Dots–Silica Nanoparticles Synthesis and their Potential Use as Biosensing and Theragnostic ApplicationsSchematic view of the fluorescence enhancement mechanism of carbon dots (a) and graphs showing the fluorescence intensity decrease in the presence of copper ions and selectivity over other metal ions (b). Adapted with permission from ref. [219] © 2017 Elsevier. Schematic illustration showing the microemulsion system used to obtain CDs/silica (c) and CDs/silica under UV light (d). CDs/silica as a ratiometric immunosensor for alpha-fetoprotein detection (e). Reproduced with permission from reference [223] © 2016 Royal Society of ChemistryBack to article page