RT Journal Article SR Electronic T1 In Vivo Cancer Dual-Targeting and Dual-Modality Imaging with Functionalized Quantum Dots JF Journal of Nuclear Medicine JO J Nucl Med FD Society of Nuclear Medicine SP 1278 OP 1284 DO 10.2967/jnumed.115.158873 VO 56 IS 8 A1 Kongzhen Hu A1 Hongliang Wang A1 Ganghua Tang A1 Tingting Huang A1 Xiaolan Tang A1 Xiang Liang A1 Shaobo Yao A1 Dahong Nie YR 2015 UL http://jnm.snmjournals.org/content/56/8/1278.abstract AB Semiconductor quantum dots (QDs), after surface modification to provide water solubility and biocompatibility, have a promising future in biomedical applications. In this study, a dual receptor–targeting dual-modality PET/near-infrared fluorescence (NIRF) probe was developed for accurate assessment of the pharmacokinetics and tumor-targeting efficacy of QDs. Methods: QDs were modified by β-Glu-RGD-BBN (RGD is arginine-glycine-aspartate acid, and BBN is bombesin) peptides and then labeled with 18F via the 4-nitrophenyl-2-18F-fluoropropionate prosthetic group. Cytotoxicity and cell-binding assay of QD-RGD-BBN were performed with PC-3 cells. In vivo dual-modality PET/NIRF imaging of prostate tumor–bearing mice was investigated using QD-RGD-BBN and 2-18F-fluoropropionyl-QD-RGD-BBN (18F-FP-QD-RGD-BBN). An in vivo biodistribution study of 18F-FP-QD-RGD-BBN was performed on normal mice. Results: QD-RGD-BBN exhibited strong red luminescence (600–800 nm) with the same maximum fluorescence wavelength (705 nm) as QD705 and slightly lower toxicity than that of QD705 in PC-3 cells at concentrations of greater than 30 μg/mL. Uptake of QD-RGD-BBN in PC-3 cells showed no significant decrease in the presence of an excess amount of dimer arginine-glycine-aspartate acid (RGD2) or bombesin(7–14) (BBN) peptide but was blocked significantly in the presence of an excess amount of NH2-RGD-BBN. Dual-function PET/NIRF imaging is able to accurately assess the biodistribution and tumor-targeting efficacy of the 18F-labeled functionalized QDs. Conclusion: The functionalized QD probe has great potential as a universal dual-targeting probe for detecting tumors in living subjects, opening up a new strategy for the development of multitargeting multimodality 18F-labeled QD probes with improved tumor-targeting efficacy.