Fluorescent nanosensors via photoinduced polymerization of hydrophobic inorganic quantum dots for the sensitive and selective detection of nitroaromatics.

We developed an efficient one-pot strategy for the preparation of hydrophilic amine-functionalized nanocomposites by using hydrophobic fluorescence quantum dots ZnS:Mn(2+)@allyl mercaptan (QDs@AM) as building blocks through novel light-induced in situ polymerization. The average size of as-prepared hydrophilic nanocomposites was ∼50 nm, which could be further tuned by varying the concentrations of the monomers. Importantly, these nanocomposites were further utilized for the facile, highly sensitive, and selective detection of nitroaromatics. The linear ranges for 2,4,6-trinitrotoluene (TNT) and 2,4,6-trinitrophenol (TNP) lie in 0.01-0.5 μg/mL and 0.05-8.0 μg/mL, respectively, barely interfered with by other nitroaromatics such as 2,4-dinitrotoluene (DNT) and nitrobenzene (NB). Moreover, the novel surface modification method developed here offered a general strategy for fabricating hydrophobic nanocomposites with hydrophilic properties and indicated various potential applications including sensing and imaging.