Other Functional Quantum Dots
Product Description
Alfa Chemistry offers other functional quantum dots, including PbS quantum dots and upconverting nanoparticle quantum dots, which can be used directly in LEDs, solar cells, bioimaging and cancer imaging.
Our products include the following:
PbS LED Quantum Dots, with a wavelength of 1300 nm and a quantum yield of >40%, can be directly applied to optoelectronic devices.
PbS Quantum Dot Solar Cells, the wavelength is 1100 nm, the quantum yield is >40%, and the solvent is toluene, which can be directly applied to optoelectronic devices.
Light Emitting Diodes (Upconverting Nanoparticle Quantum Dots), the wavelength is 545-655 nm, the solvent is organic solvent or water, and can be directly applied to light-emitting diodes.
Quantum Dots Biological Imaging (Upconverting Nanoparticles), with a wavelength of 800 nm and a solvent of toluene, can be directly applied to biological imaging.
Quantum Dots Cancer Imaging (Upconverting Nanoparticle Quantum Dots), the wavelength is 545 nm, the solvent is water, which can be directly applied to cancer imaging.
Features
Uniform particle size
Broad absorption spectrum
Symmetrical emission spectrum
High and stable fluorescence intensity
Applications
Bioimaging
Chatterjee et al. developed a method to perform in vivo, dynamic imaging of single cells implanted in vivo by using a novel fluorescent tag called upconversion nanoparticles (UCN). These unique nanoparticles allow visualization through the intact skin and can be seen to a significant depth of several hundred microns. In addition, these are biocompatible labels and have exceptional fluorescence stability under in vivo conditions, allowing continuous imaging for hours.
Upconversion nanoparticles (UCN) are phosphorus nanocrystals doped with transition metal, lanthanide or actinide ions. The doped ions (here ytterbium (Yb3+) and erbium (Er3+)) each absorb a low-energy photon when excited with a near-infrared laser. Yb3+ non-radiometrically transfers its excess energy to Er3+, which is excited to a higher level. This is emitted as high-energy light when Er3+ returns to the ground. Since upconversion (emitted energy > excitation energy) is absent in tissues, these nanoparticles exhibit particularly high signal-to-background ratios and have been used for immunohistochemistry, imaging of elegant animals, and detection of drugs of abuse, bacterial antigens, human chorionic gonadotropins, and nucleic acids.
Fig. 1 Schematic of UCN showing the process of upconversion. (Chatterjee et al., 2012)
Light-emitting diodes (LEDs)
Cao et al. report wide-field upconversion microscopy using incoherent excitation of 970 nm light-emitting diodes (LEDs) on single nanoparticle sensitivities. Due to its broad emission spectrum, LED excitation is about 3 times less effective for UCNPs and produces high background compared to laser illumination. To address this issue, time-gated luminescence detection was used to eliminate the residual background of the LED light source, so that individual UCNPs with high photoreceptor (Yb3+) doping and inert shell protection became clearly discernible under LED excitation at 1.18 W cm-2. Hydrophilic UCNPs were obtained by a simple ligand exchange protocol for the polysaccharide coating to demonstrate imaging of cellular uptake using LED excitation.
Fig. 2 TEM and LED-excited UCL images of (a) NaY0.79Yb0.20Tm0.01F4, (b) NaYb0.99Tm0.01F4 and (c) NaYb0.99Tm0.01F4@NaYF4 UCNPs. (Cao et al., 2020)
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
- Chatterjee, D. K. , and Z. Yong . Use of upconverting fluorescent nanoparticles for bioimaging[J]. Proceedings of SPIE - The International Society for Optical Engineering, 2012, 8272(1):2.
- Cao, Y. , et al. Light-emitting diode excitation for upconversion microscopy: a quantitative assessment[J]. 2020.
* It should be noted that our service is only used for research, not for clinical use.
