Facile Synthesis of Gd-Cu-In-S/ZnS Bimodal Quantum Dots with Optimized Properties for Tumor Targeted Fluorescence/MR In Vivo Imaging.

Abstract

Dual-modal imaging techniques have gained intense attention for their potential role in the dawning era of tumor early accurate diagnosis. Chelate-free robust dual-modal imaging nanoprobes with high efficiency and low toxicity are of essential importance for tumor targeted dual-modal in vivo imaging. It is still a crucial issue to endow Cd-free dual-modal nanoprobes with bright fluorescence as well as high relaxivity. Herein, a facile synthetic strategy was developed to prepare Gd-doped CuInS/ZnS bimodal quantum dots (GCIS/ZnS, BQDs) with optimized properties. The fluorescent properties of the GCIS/ZnS BQDs can be thoroughly optimized by varying reaction temperature, aging time, and ZnS coating. The amount of Gd precursor can be well-controlled to realize the optimized balance between the MR relaxivity and optical properties. The obtained hydrophobic GCIS/ZnS BQDs were surface engineered into aqueous phase with PEGylated dextran-stearyl acid polymeric lipid vesicles (PEG-DS PLVs). Upon the phase transfer, the hydrophilic GCIS/ZnS@PLVs exhibited pronounced near-infrared fluorescence as well as high longitudinal relaxivity (r1 = 9.45 mM(-1) S(-1)) in water with good colloidal stability. In vivo tumor-bearing animal experiments further verified GCIS/ZnS@PLVs could achieve tumor-targeted MR/fluorescence dual-modal imaging. No toxicity was observed in the in vivo and ex vivo experiments. The GCIS/ZnS@PLVs present great potential as bimodal imaging contrast agents for tumor diagnosis.

• Authors: Weitao Yang, Weisheng Guo, Xiaoqun Gong, Bingbo Zhang, Sheng Wang, Na Chen, Wentao Yang, Yu Tu, Xiangming Fang, Jin Chang
• Journal: ACS applied materials & interfaces (ACS Appl Mater Interfaces) Vol. 7 Issue 33 Pg. 18759-68 (Aug 26 2015) ISSN: 1944-8252 [Electronic] United States
• PMID: 26257133 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Contrast Media
• Dextrans
• Stearic Acids
• Sulfides
• Unilamellar Liposomes
• Zinc Compounds
• Indium
• Polyethylene Glycols
• stearic acid
• Copper
• Gadolinium
• zinc sulfide

Topics

• Animals
• Cell Line, Tumor
• Contrast Media (chemical synthesis, chemistry, metabolism)
• Copper (chemistry)
• Dextrans (chemistry)
• Disease Models, Animal
• Gadolinium (chemistry)
• Humans
• Indium (chemistry)
• Magnetic Resonance Imaging
• Mice
• Mice, Nude
• Neoplasms (diagnosis, pathology)
• Optical Imaging
• Polyethylene Glycols (chemistry)
• Quantum Dots (chemistry)
• Stearic Acids (chemistry)
• Sulfides (chemistry)
• Tissue Distribution
• Unilamellar Liposomes (chemistry, metabolism)
• Zinc Compounds (chemistry)