Cesium-lead-halide perovskite quantum dots (PQDs) are a highly promising class of the next-generation optical material for bioimaging applications. Herein, we present a nanocomposite strategy for the design of water-soluble, highly luminescence CsPbBr3 PQD nanocomposites without modifying the crystal symmetry and photoluminescence (PL) property. Water-soluble PQDs are reproducibly synthesized via encapsulating CsPbBr3 PQDs with polystyrene-block-poly(ethylene-ran-butylene)-block-polystyrene (PS-PEB-PS) and poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol (PEG-PPG-PEG). In the reported design, the polystyrene triblock polymers strongly interact with the hydrophobic parts of PQDs, and the water-soluble PEG moiety acts as a protection layer to effectively prevent degradation of PQDs in water. The outer shell PEG layer also helps to develop biocompatible PQDs. Reported data indicate that encapsulating CsPbBr3 PQDs with a polymer helps to improve the photoluminescence quantum yield (PLQY) from 83% to 88%, which may be due to a decrease in the surface defects after the effective polymer coating. Experimental data show that the PL intensity from CsPbBr3 PQD nanocomposites remains unchanged even after 30 days of exposure in air. Similarly, reported data indicate that nanocomposites retain their luminescence properties in water for the first 8 days and then decrease slowly to 60% of its initial PL intensity after one month. On the other hand, the PL emission for the PQD without polymer encapsulation is completely quenched within a few hours. Exosomes are a highly promising avenue for accessing tumor type and stage and monitoring cancer treatment response. Reported data reveal that anti-CD63 antibody-attached PQD nanocomposites are capable of tracking triple-negative MDA-MB-231 breast tumor-derived exosomes via binding using anti-CD63 antibody and selective green luminescence imaging using PQD nanocomposites.
Keywords: air stable CsPbBr3 quantum dots; green luminescence imaging; selective imaging of exosomes; triple-negative breast tumor-derived exosomes; water-soluble perovskite nanocomposites.