Cadmium-based Quantum Dots
Product Description
Alfa Chemistry offers our customers a wide range of quantum dots. Our Cd-based products are designed to couple cadmium-containing quantum dots with specific moieties to expand their applications in multiple fields. Our products include anti-human CD3/CD4/CD8 conjugated Cd quantum dots, amino Cd quantum dots, anti-human DNP/EpCam/Fluorescein conjugated Cd quantum dots, PDDA Cd quantum dots, streptavidin quantum dots and PEG Cd quantum dots are available in wavelengths from 450-665 nm for applications in biomarkers, cell imaging, fluorescent probes, etc.
Applications
Biomedical Applications
The increasing potential of quantum dots (QDs) in biomedical applications has raised great concern about their toxicological effects. Therefore, it is necessary to understand the underlying toxicity mechanisms of quantum dots. In this work, Hu et al. comprehensively investigated three CdSe/ZnS QDs (COOH CdSe/ZnS 525, NH2 CdSe/ZnS 525 and NH2 CdSe/ZnS 625) using confocal laser scanning microscopy, reactive oxygen species (ROS) measurements and cell viability assays in Phanerochaete chrysosporium (P. chrysosporium) bioaccumulation and toxicity. The results of confocal laser scanning microscopy analysis showed that all CdSe/ZnS QDs, with concentrations ranging from 10 to 80 nM, were able to accumulate heavily in the mycelium and induce ROS production, showing direct toxicity to P. chrysosporium. Bioaccumulation and toxicity of CdSe/ZnS QDs showed dose-dependent and time-dependent effects on P. chrysosporium. In addition, the cytotoxicity induced by CdSe/ZnS QDs was also related to their physicochemical properties, including particle size and surface charge. The cytotoxicity of small-sized NH2 CdSe/ZnS 525 was greater than that of large-sized NH2 CdSe/ZnS 625, while smaller negatively charged NH2 CdSe/ZnS 525 was more cytotoxic than the larger negatively charged COOH CdSe/ZnS 525.
Fig. 1 TEM images of COOH CdSe/ZnS 525 (a), NH2 CdSe/ZnS 525 (b), and NH2 CdSe/ZnS 625 (c), respectively. (Hu et al., 2017)
Biological Labeling
Semiconductor quantum dots are a promising class of materials in the labeling of biological systems. Chaves et al. demonstrated the labeling pattern of living Trypanosoma cruzi (T. cruzi) using PEGylated CdS/Cd(OH)2 fluorescent nanocrystals. The analysis obtained by confocal fluorescence microscopy and transmission electron microscopy showed that only the endocytic pathway of the parasite was labeled. After incubation with a CdS/Cd(OH)2-PEG suspension, the parasite was alive. Labeling T. cruzi with quantum dots contributes to a better understanding of the endocytosis process and also to the understanding of cell differentiation.
Fig. 2 (a) Endocytic pathway of T. cruzi epimastigote. (b) TEM of T. cruzi parasites showing the accumulation of CdS/Cd(OH)2–PEG QDs (arrow) inside the tubular structure resembling the cytostome (CY) in close association with reservosomes (R). (c) Overlay of the image of fluorescence microscopy and differential interference contrast showing the strong QDs labeling in the cytostome (CY). (d) The same image showing only fluorescence staining. (Chaves et al., 2008)
Alfa Chemistry can provide a variety of complex and customized fluorescent quantum dot products. Our products involve perovskites precursors, perovskites quantum dots, quantum dot kit, single layer quantum dots, upconverting nanoparticles and other fluorescent quantum dots. Alfa Chemistry provides products with high fluorescence quantum yield, stable quality and relatively low price. Our products are constantly updated. If the product you need is not in our catalog, please feel free to contact us, we provide relevant custom services.
References
- Hu, Liang, et al. Bioaccumulation and toxicity of CdSe/ZnS quantum dots in Phanerochaete chrysosporium[J]. Colloids and Surfaces B: Biointerfaces, 2017, 159: 303-311.
- Chaves, C. R., et al. Application of core-shell PEGylated CdS/Cd (OH)2 quantum dots as biolabels of Trypanosoma cruzi parasites[J]. Applied surface science, 2008, 255(3): 728-730.
* It should be noted that our service is only used for research, not for clinical use.
