Synthesis and characterization of ZnS:Mn/ZnS core/shell nanoparticles for tumor targeting and imaging in vivo

Abstract

Fluorescence imaging technique has been used for imaging of biological cells and tissues in vivo. The Cd-free luminescent quantum dots conjugating with a cancer targeting ligand has been taken as a promising biocompatibility and low cytotoxicity system for targeted cancer imaging. This work reports the synthesis of fluorescent-doped core/shell quantum dots of water-soluble manganese-doped zinc sulfide. Quantum dots of manganese-doped zinc sulfide were prepared by nucleation doping strategy, with 3-mercaptopropionic acid as stabilizer at 90 in aqueous solution. The manganese-doped zinc sulfide nanoparticles exhibit strong orange fluorescence under UV irradiation, resistance to photo-bleaching, and low-cytotoxicity to HeLa cells. The structure and optical properties of nanoparticles were characterized by scanning electron microscope, X-ray diffraction, dynamic light scattering, and photoluminescence emission spectroscopy. Manganese-doped zinc sulfide nanoparticles conjugated with folic acid using 2,2'-(ethylenedioxy)-bis-(ethylamine) as the linker. The covalent binding of both 2,2'-(ethylenedioxy)-bis-(ethylamine) and folic acid on the surface of manganese-doped zinc sulfide nanoparticles probed by Fourier transform infrared spectroscopy detection. Furthermore, in vitro cytotoxicity assessment of manganese-doped zinc sulfide-folic acid probes use HeLa cells. The obtained fluorescent probes (manganese-doped zinc sulfide) were used for tumor targeting and imaging in vivo. The manganese-doped zinc sulfide-folic acid fluorescent probes which targeting the tumor cells in the body of nude mouse tumor model would emit orange fluorescence, when exposed to a 365 nm lamp. We investigate the biodistribution of the manganese-doped zinc sulfide-folic acid fluorescent probes in tumor mouse model by measuring zinc concentration in tissues. These studies demonstrate the practicality of manganese-doped zinc sulfide-folic acid fluorescent probes as promising platform for tumor targeting and imaging in vivo.

Colloidal silicon quantum dots: from preparation to the modification of self-assembled monolayers (SAMs) for bio-applications

“…By doping zincbased QDs with heavy metal ions, strong emission in the visible region has been achieved. 227 ZnS:Mn/ZnS core-doped core-shell QDs were used in vivo for tumour imaging, 228 and recently Maity et al compared the performance of three doped QD materials (Mn doped ZnS, Mn doped ZnSe and Cu doped InZnS) in vitro. 229 Silicon is an attractive material for the preparation of cadmium free QDs because it is non-toxic in its bulk form and is readily degraded to silicic acid, which can be excreted in the urine.…”

Iron–gold alloy nanoparticles serve as a cornerstone in hyperthermia-mediated controlled drug release for cancer therapy

“…Single metal as well as metal alloy nanoparticles are exploited in the fields of catalysis, 5 imaging, 6 and biomedical 7 or tissue engineering. 8,9 A variety of nanoparticles such as gold, titania, silica, iron, and zinc sulfide have found applications in immunocytochemistry, 10 antibacterial medications, 11 fluorescent dyes, 12 drug delivery, 13,14 and biological imaging, 15 respectively. Additionally, the nano size of these particles makes it easier for them to be ingested by cells, where they can conveniently interact with cellular components and provide useful information about biological processes.…”

Folic acid targeted Mn:ZnS quantum dots for theranostic applications of cancer cell imaging and therapy

“…6,7,9 Several researchers have explored novel approaches for the synthesis of water-soluble QDs through the selection of appropriate stabilizers such as 3-mercaptopropionic acid (MPA), mercaptoacetic acid, thioglycolic acid (TGA), polysaccharide copolymers, etc. 4,13 However, some researchers observed that the quantum yield obtained from QDs stabilized by thiol-groups is usually low. [14][15][16] Furthermore, the thiol-QD bond is also reported not to be very stable and precipitates readily on being dialyzed against buffer solution and water with time.…”