Exploring
the synthesis of new biocompatible quantum dots (QDs)
helps in overcoming the intrinsic toxicity of the existing QDs composed
of highly toxic heavy metals (e.g., Cd, Hg, Pb, etc.) and is particularly
interesting for the future practical application of QDs in biomedical
imaging. Hence, in this report, a new one-pot approach to oil-soluble
(highly toxic heavy metal-free) highly luminescent quaternary Zn–Ag–In–Se
(ZAISe) QDs was designed. Their photoluminescence (PL) emission
could be systematically tuned from 660 to 800 nm by controlling the
Ag/Zn feed ratio, and their highest PL quantum yield is close to 50%
after detailed optimization. Next, by using biodegradable RGD peptide
(arginine–glycine–aspartic
acid)-modified N-succinyl-N′-octyl-chitosan
(RGD-SOC)
micelles as a water transfer agent, the versatility of these quaternary
ZAISe QDs for multiscale bioimaging of micelles (namely, in
vitro and in vivo evaluating the tumor targeting
of drug carriers) was further explored, as a promising alternative
for Cd- and Pb-based QDs.