Ratiometric two-photon excited photoluminescence of quantum dots triggered by near-infrared-light for real-time detection of nitric oxide release in situ

摘要

Probe-donor integrated nanocomposites were developed from conjugating silica-coated Mn2+:ZnS quantum dots (QDs) with MoS2 QDs and photosensitive nitric oxide (NO) donors (Fe4S3(NO)(7)(-), RBS). Under excitation with near-infrared (NIR) light at 808 nm, the Mn2+:ZnS@SiO2/MoS2-RBS nanocomposites showed the dual-emissive two-photon excited photoluminescence (TPEPL) that induced RBS photolysis to release NO in situ. NO caused TPEPL quenching of Mn2+:ZnS QDs, but it produced almost no impact on the TPEPL of MoS2 QDs. Hence, the nanocomposites were developed as a novel QDs-based ratiometric TPEPL probe for real-time detection of NO release in situ. The ratiometric TPEPL intensity is nearly linear (R-2 = 0.9901) with NO concentration in the range of 0.01 similar to 0.8 mu M, which corresponds to the range of NO release time (0 similar to 15 min). The detection limit was calculated to be approximately 4 nM of NO. Experimental results confirmed that this novel ratiometric TPEPL probe possessed high selectivity and sensitivity for the detection of NO against potential competitors, and especially showed high detection performance for NIR-light triggered NO release in tumor intracellular microenvironments. These results would promote the development of versatile probe-donor integrated systems, also providing a facile and efficient strategy to real-time detect the highly controllable drug release in situ, especially in physiological microenvironments. (C) 2016 Elsevier B.V. All rights reserved.