Cadmium selenide quantum dots: synthesis, …
Synthesis of Cadmium Selenide Quantum Dot …
Wu et al. reported polysaccharide-based hybrid nanogels that combine functional building blocks for optical pH-sensing, cancer cell imaging, and controlled drug release within a single nanoparticle system for combined diagnosis and therapy. The hybrid nanogels were synthesized by in-situ immobilization of CdSe QDs in the interior of the dual responsive (pH and temperature) hydroxypropylcellulose -poly (acrylic acid) (HPC-PAA) semi-interpenetrating polymer networks. The HPC-PAA-CdSe hybrid nanogels combine a strong trap emission at 741 nm for sensing physicochemical environment in a pH dependent manner and a visible excitonic emission at 592 nm for mouse melanoma B16F10 cell imaging. The hybrid nanogels also provide excellent stability as a drug carrier. They not only provide a high drug loading capacity for a model anticancer drug, temozolomide, but also offer a pH-triggered sustained-release of the drug molecules in the gel network.
Synthesis of Cadmium Selenide Quantum Dot Nanoparticles
Tian et al. reported the design of drug-loaded liposome-QD hybrid vesicles by incorporating TOPO-coated CdSe/ZnS QDs into two types of lipid bilayers, namely, the 'rigid' disteroylphosphatidylcholine and a fluid-phase bilayer of egg PC. Structural characterization of QD hybrid-vesicles using atomic force microscopy revealed that the QD were incorporated within the lipid membranes of the vesicles. The encapsulation of hydrophilic small molecules (carboxyfluorescein) in the internal aqueous phase of the L-QD hybrids showed different degrees of release in buffer and serum, depending on the type of lipid used. The presence of QD in the lipid bilayer increased the carboxyfluorescein release from the EPC fluid bilayer. In contrast, (DSPC) L-QD hybrids showed a higher stability under the same conditions with minimal carboxyfluorescein leakage. In addition, (DSPC) L-QD hybrids showed no changes in size over a period of three weeks. Finally, doxorubicin (Dox) was loaded into L-QD hybrids using the osmotic gradient technique with at least 97% loading efficiency. The fluorescence spectrum of Dox was simultaneously detected with that of green-emitting QD that indicated the coexistence of QD and Dox in a single vesicle system. Overall, the drug-loaded L-QD-Dox hybrid vesicles provide a promising multifunctional delivery vector capable of transporting combinations of therapeutic and diagnostic modalities.
Quantum dots - Cadmium selenide quantum dots
Ourresults also suggest that under controlled conditions, directwater-soluble TGA-CdSe QDs can be potentially employed for bio-imagingcolo-205 cancer cells with minimal adverse effects.
selenide and cadmium selenide/cadmium sulfide quantum dots:
(a) Absorption and emission of rhodamine red, a common organic dye, and genetically-encoded DsRed2 protein. (b) Absorption and emission of different QD dispersions. The black line shows the absorption of the 510-nm-emitting QDs. (c) Photo demonstrating the size-tunable luminescence properties and spectral range of the six QD dispersions plotted in b versus CdSe core size. All samples were excited at 365 nm. Reprinted by permission from Macmillan Publishers Ltd: Nature Materials (Medintz IL, Uyeda HT, Goldman ER, Mattoussi H. Quantum dot bioconjugates for imaging, labelling and sensing. Nat Mater. 2005; 4: 435-46., ), copyright 2005.
(CdSe)ZnS Core−Shell Quantum Dots: Synthesis …
Moreover, confocal microscopy analysis conducted to evaluate theintracellular uptake of TGA-CdSe QDs reveal that the TGA-CdSe QDs wereuniformly distributed within the cytosolic side of cell membranes.