A simplistic approach to green future with eco-friendly luminescent carbon dots and their application to fluorescent nano-sensor ‘turn-off’ probe for selective sensing of copper ions

Zero-dimensional fluorescent nanoparticles having specificity as molecular probe appears to be strategically balanced fluorescent nano-probes. In this work, purified lemon extract and L-arginine have been thermally coupled for the extremely acute detection of Cu^2 + in aqueous medium. The Cu^2 + ions may be captured by the amino groups on the surface of the nano-sensor to form cupric ammine complex resulting in quenched fluorescence via an inner filter effect. Our proposed nano-probe is N-doped carbon dots (NCDs) which are efficiently selective as fluorescent chemosensor due to enormous binding affinity towards Cu^2 + in a wide range of concentration (0.05–300 μM) within a few minutes.