Carbon nanotube–quantum dot nanocomposites as new fluorescence nanoparticles for the determination of trace levels of PAHs in water

Amplification of fluorescence is a nanoscale phenomenon which is particularly pronounced in close proximity to metal nanostructures. We have demonstrated for first time that fluorescence amplification can also be produced by single-walled carbon nanotube–quantum dot nanocomposites (SWCNT–QDs). Concretely we exploit the adsorption capabilities of SWCNTs to facilitate the interaction of analytes with the nanoparticle. The fluorescence amplification mechanism is discussed in the paper. The analytical potential of these nanocomposites has been demonstrated for the detection of trace levels of polycyclic aromatic compounds (PAHs) in river water samples. Compared with QDs nanoparticles, the fluorescence enhancement achieved with the SWCNT–QDs nanocomposites was 3.6–5.5 times higher.