Enhanced photoluminescence of water-soluble Mn-doped ZnS quantum dots by thiol ligand exchange

2012 ◽  
Vol 519-520 ◽  
pp. 73-77 ◽  
Author(s):  
Jinju Zheng ◽  
Fengmei Gao ◽  
Guodong Wei ◽  
Weiyou Yang
Keyword(s):  
Quantum Dots ◽  
Ligand Exchange ◽  
Water Soluble ◽  
Enhanced Photoluminescence ◽  
Mn Doped ◽  
Thiol Ligand

A novel route to photoluminescent, water-soluble Mn-doped ZnS quantum dots via photopolymerization initiated by the quantum dots

2008 ◽  
Vol 19 (48) ◽  
pp. 485602 ◽  
Author(s):  
Xufeng Liu ◽  
Xiuyuan Ni ◽  
Jiao Wang ◽  
Xinghai Yu
Keyword(s):  
Quantum Dots ◽  
Water Soluble ◽  
Mn Doped

Ultrasonic synthesis of Mn-doped CsPbCl3 quantum dots (QDs) with enhanced photoluminescence

2019 ◽  
Vol 94 ◽  
pp. 41-46 ◽  
Author(s):  
Changhong Li ◽  
Ye Li ◽  
Tianliang Zhou ◽  
Rong-Jun Xie
Keyword(s):  
Quantum Dots ◽  
Ultrasonic Synthesis ◽  
Enhanced Photoluminescence ◽  
Mn Doped

scholarly journals Cadmium-Free Quantum Dots as Fluorescent Labels for Exosomes

Sensors ◽  
2018 ◽  
Vol 18 (10) ◽  
pp. 3308 ◽  
Author(s):  
Garima Dobhal ◽  
Deanna Ayupova ◽  
Geoffry Laufersky ◽  
Zeineb Ayed ◽  
Thomas Nann ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Cell Line ◽  
Ligand Exchange ◽  
Fluorescent Microscopy ◽  
Fluorescent Labeling ◽  
Water Soluble ◽  
Exchange Method ◽  
Cell Processes ◽  
Monocyte Cell ◽  
Detection Of Biomarkers

Quantum dots are attractive alternatives to organic fluorophores for the purposes of fluorescent labeling and the detection of biomarkers. They can also be made to specifically target a protein of interest by conjugating biomolecules, such as antibodies. However, the majority of the fluorescent labeling using quantum dots is done using toxic materials such as cadmium or lead due to the well-established synthetic processes for these quantum dots. Here, we demonstrate the use of indium phosphide quantum dots with a zinc sulfide shell for the purposes of labeling and the detection of exosomes derived from the THP-1 cell line (monocyte cell line). Exosomes are nano-sized vesicles that have the potential to be used as biomarkers due to their involvement in complex cell processes. However, the lack of standardized methodology around the detection and analysis of exosomes has made it difficult to detect these membrane-containing vesicles. We targeted a protein that is known to exist on the surface of the exosomes (CD63) using a CD63 antibody. The antibody was conjugated to the quantum dots that were first made water-soluble using a ligand-exchange method. The conjugation was done using carbodiimide coupling, and was confirmed using a range of different methods such as dynamic light scattering, surface plasmon resonance, fluorescent microscopy, and Fourier transform infrared spectroscopy. The conjugation of the quantum dot antibody to the exosomes was further confirmed using similar methods. This demonstrates the potential for the use of a non-toxic conjugate to target nano-sized biomarkers that could be further used for the detection of different diseases.

scholarly journals Effect of Micelle Encapsulation on Toxicity of CdSe/ZnS and Mn-Doped ZnSe Quantum Dots

Coatings ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 895
Author(s):  
Qirui Fan ◽  
Abhilasha Dehankar ◽  
Thomas K. Porter ◽  
Jessica O. Winter
Keyword(s):  
Heavy Metals ◽  
Quantum Dots ◽  
Ligand Exchange ◽  
Surface Coatings ◽  
Oxygen Species ◽  
Significant Toxicity ◽  
Toxicity Response ◽  
Protective Polymer ◽  
Dose Dependent ◽  
Mn Doped

The optical properties of quantum dots (QD) make them excellent candidates for bioimaging, biosensing, and therapeutic applications. However, conventional QDs are comprised of heavy metals (e.g., cadmium) that pose toxicity challenges in biological systems. Synthesising QDs without heavy metals or introducing thick surface coatings, e.g., by encapsulation in micelles, can reduce toxicity. Here, we examined the toxicity of micelle encapsulated tetrapod-shaped Mn-doped ZnSe QDs, comparing them to 3-mercaptopropionic acid (MPA)-capped Mn-doped ZnSe QDs prepared by ligand exchange and commercial CdSe/ZnS QD systems that were either capped with MPA or encapsulated in micelles. HepG2 cell treatment with MPA-coated CdSe/ZnS QDs resulted in a dose-dependent reduction of viability (MTT assay, treatment at 0–25 μg/mL). Surprisingly, no reactive oxygen species (ROS) or apoptotic signaling was observed, despite evidence of apoptotic behavior in flow cytometry. CdSe/ZnS QD micelles showed minimal toxicity at doses up to 25 μg/mL, suggesting that thicker protective polymer layers reduce cytotoxicity. Despite their shape, neither MPA- nor micelle-coated Mn-doped ZnSe QDs displayed a statistically significant toxicity response over the doses investigated, suggesting these materials as good candidates for bioimaging applications.

Sign in / Sign up

Export Citation Format

Share Document