Oil Dispersible Upconverting Nanoparticles
Alfa Chemistry offers oil-soluble up-conversion nanoparticles composed of NaYREF4 (RE: Yb, Er, Tm, Gd, Mn, Lu) with an optimal excitation wavelength of 975 nm. The sensitizing ion is Yb3+ and the activating ion is Er3+ or Tm3+. By adjusting the doping concentration of each ion, the luminescence at specific wavelengths has been optimized. The products have uniform particle size, high luminescence quantum efficiency and good photostability. After surface modification, they can be used for fluorescence imaging, bio-detection, photodynamic therapy, and light-controlled remote release of anti-cancer drugs and biomolecules.
Upconversion nanoparticles (UCNPs) are inorganic materials that are exceptionally photostable and have the unique ability to convert infrared radiation to visible light through sequential absorption and energy transfer of multiple infrared photons. UCNPs produce intense anti-Stokes photoluminescence that can be measured by a simple fluorescence readout. Henna et al. demonstrated the ability to array multiple antibodies in the form of printed on the bottom of a microtiter plate and evaluated the performance of an array-based immunoassay using a mixture of secondary antibody-coated UCNPs, each specific for one of the analytes measured. To demonstrate the performance of this platform, prostate-specific antigen (PSA), thyroid-stimulating hormone (TSH) and luteinizing hormone (LH) were selected as model analytes. PSA is widely used as a serum biomarker to assist in the diagnosis of prostate cancer and to assess patient response to treatment and cancer recurrence. TSH is essential for maintaining normal thyroid function, and it is used to diagnose primary and secondary hypothyroidism and hyperthyroidism. LH levels are used to determine menopause, to determine ovulation, and to diagnose pituitary disorders. Increased LH concentrations can be measured in renal failure, cirrhosis, hyperthyroidism and severe starvation, while low levels may indicate infertility in both men and women.
Fig.1 Multianalyte array-in-well immunoassay principle. Biotinylated antibodies (Bio-Ab) were printed on streptavidin-coated (SA) microtiter wells. (Henna et al., 2012)
Upconverted UV/visible light can induce photoreactions of conventional UV/visible light sensitive compounds. This process is known as UCNP-assisted photochemistry. Chen et al. demonstrated experimentally that the combination of UCNPs and photobases can control pH by NIR light. The reason why UCNPs can effectively aid the photolysis of Ru complexes is that the absorption of Ru complexes overlaps with the emission spectrum of UCNP. The UCNPs convert NIR light into blue light, which triggers the reaction of [Ru(bpy)2(PPh3)(BuNH2)]2+ ( bpy = 2,2’ bipyridine, PPh3 = triphenylphosphine, BuNH2 = n-butylamine) (Ru-A) in the release of n-butylamine. A photonic upconversion pH control strategy was further developed to control the solubilization of pH-sensitive PAA hydrogels. Not only Ru-A but also many other photo acids/photobases can change the pH of the solution after light irradiation. In addition, photonic upconversion pH manipulation can induce swelling of not only pH-sensitive hydrogels but also stimulate other pH-responsive materials such as micelles, capsules and supramolecules.
Fig. 2 The blue emission from UCNPs triggers the cleavage of the Ru photobase (Ru-A) and induces pH change. (Chen et al., 2016)
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.
- Henna, et al. Quantitative Multianalyte Microarray Immunoassay Utilizing Upconverting Phosphor Technology[J]. Analytical Chemistry, 2012, 84(20):8628-8634.
- Chen, Z. , et al. Manipulating pH using near-infrared light assisted by upconverting nanoparticles[J]. Chemical Communications, 2016, 52(97).
* It should be noted that our service is only used for research, not for clinical use.