The exploration of original computed tomography (CT) imaging
contrast agents with enhanced sensitivity and specificity is currently one of the major challenging tasks for
precision medicine. Herein, we develop an innovative nanoprobe of
dendrimer-stabilized
gold nanoparticles (Au DSNs) linked with
folic acid (FA) as a targeting
ligand and
diatrizoic acid (DTA) for specific enhanced
tumor CT imaging. In current work,
poly(amidoamine) (PAMAM)
dendrimers of generation 5 (G5) with
amine termini were adopted to entrap Au NPs through a stepwise complexation/reduction method to achieve a higher Au loading than the conventional one-step complexation/reduction method. The prepared [(Au0)120-G5.NH2] NPs were sequentially functionalized with
diatrizoic acid (DTA), a typical CT
contrast agent based on
iodine(I), FA through a poly(
ethylene glycol) (PEG) spacer, and carboxylated PEG monomethyl
ether (
mPEG-COOH), ended with complete acetylation of the leftover
dendrimer amine termini. The generated Au DSNs-DTA-FA (Au core diameter = 5.9 nm) were thoroughly characterized. Our data reveal that the Au DSNs-DTA-FA containing Au and I dual radiodense elements are stable, display enhanced CT imaging performance, much higher than the single-radiodense elemental material solely based on Au or I, and possess a quite good cytocompatibility. With the demonstrated FA-rendered specific targeting, the developed Au DSNs-DTA-FA can be employed as a highly efficient nanoprobe for targeted enhanced CT imaging of
cancer cells and a subcutaneous
tumor model. Overall, the created Au DSNs-DTA-FA may be a powerful nanoprobe for specific enhanced CT imaging of various kinds of FA receptor-expressing
tumors or biosystems.