10-Fold Quantum Yield Improvement of Ag₂S Nanoparticles by Fine Compositional Tuning
Ag₂S semiconductor nanoparticles (NPs) are near-infrared luminescent probes with outstanding properties (good biocompatibility, optimum spectral operation range, and easy biofunctionalization) that make them ideal probes for in vivo imaging. Ag₂S NPs have, indeed, made possible amazing challenges including in vivo brain imaging and advanced diagnosis of the cardiovascular system. Despite the continuous redesign of synthesis routes, the emission quantum yield (QY) of Ag₂S NPs is typically below 0.2%. This leads to a low luminescent brightness that avoids their translation into the clinics. In this work, an innovative synthetic methodology that permits a 10-fold increment in the absolute QY from 0.2 up to 2.3% is presented. Such an increment in the QY is accompanied by an enlargement of photoluminescence lifetimes from 184 to 1200 ns. The optimized synthetic route presented here is based on a fine control over both the Ag core and the Ag/S ratio within the NPs. Such control reduces the density of structural defects and decreases the nonradiative pathways. In addition, we demonstrate that the superior performance of the Ag₂S NPs allows for high-contrast in vivo bioimaging.
Using Edinburgh Instruments FLS920, you can download the full article and read the results of this research.
At Edinburgh Instruments we manufacture a variety of spectrometers that are dedicated to the measurement of fluorescence lifetimes. You can view our full range of fluorescence spectrometers here .
If you would like to stay up to date with our latest news, research and products, why not follow us on social media and sign up to our infrequent eNewsletter below.