Construction, release and cellular imaging application of triethylamine-responsive fluorescent quantum dots based on supramolecular self-assembly.

[Display omitted] • Triethylamine-responsive QDs based on supramolecular self-assembly was synthesized. • Fluorescence of QD621/ZnS/HPEISA increased greatly after adding triethylamine. • QD621/ZnS/HPEISA supramolecular self-assembly was cleaved by excess triethylamine. • Released QDs/HPEI nanocomposites could easily be endocytosed by the L929 cells. A new strategy for the construction, release and cellular imaging application of triethylamine-responsive fluorescent quantum dots (QDs) based on supramolecular self-assembly has been described. The supramolecular self-assembly (HPEI/SA), which was constructed through the electrostatic interactions between terminal amine groups of hyperbranched polyethylenimines (HPEI) and carboxylic acid groups of stearic acid (SA), first captured aqueous Zn2+ ions into the hydrophilic dendritic core and subsequently encapsulated QDs/S2- by the complexation interactions and reactions between Zn2+ and S2- on QDs. Due to the pH-responsive property of the HPEI/SA supramolecular self-assembly, the fluorescence of encapsulated QDs is sensitive to the triethylamine/SA mole ratio, and the encapsulated QDs can be released to the aqueous phase by cleaving HPEI/SA. The resulting fluorescent QDs/HPEI nanocomposites show promising prospects in bioimaging. [ABSTRACT FROM AUTHOR]