Probing the structure of photoluminescent Ag2S-based quantum dots in hepatic cells

Silver sulphide (Ag2S) quantum dots (QD) are semiconductor nanocrystal with outstanding optical properties as a broad absorption spectrum and narrow and tuneable emission in the Near-Infrared domain. Ag2S is a non-toxic material, which makes these QD eligible for in vivo imaging and drug delivery. However, their stability in biological systems and their biocompatibility need to be assessed before any in vivo application. We are currently developing Ag2S QDs with different sizes and coatings, in order to optimize their optical properties. We propose to make use of XAFS to investigate the stability of these different formulations in cellular models, including in 3D cell cultures mimicking the liver. This information, corroborated by their photophysical characterization and by cytotoxicity assays, will help us identify the best candidates for the development of nanoplatforms for imaging and therapy.