Functional Quantum Dots
Product Description
Alfa Chemistry offers functional quantum dots that can be directly utilized in specific applications, including bio-imaging, fluorescent labeling, solar cells, light emitting diodes, and more.
The types of quantum dots we offer include:
Quantum Dots for LEDs with wavelengths from 450 nm to 625 nm and quantum yields from 75% to 80%.
Quantum Dot Labeling, wavelengths from 360 nm to 500 nm, widely used in immunohistochemistry and indirect immunofluorescence analysis.
Other Functional Quantum Dots, including PbS LED Quantum Dots and Quantum Dots Biological Imaging (Upconverting Nanoparticles Quantum Dots).
Features
Uniform particle size
Broad absorption spectrum
Symmetrical emission spectrum
High and stable fluorescence intensity
Applications
Antibody-based Biosensors for QDs
Antibodies are immunoglobulins produced by antigenic stimuli and have specificity and affinity to recognize and defend against pathogens in the immune system. Using antibodies as recognition elements for biosensors, a single antibody molecule can be attached to multiple QDs to enhance the dipole interactions between particles. The QDs-antibody conjugates can then be used as probes to specifically recognize and bind pathogenic bacteria, and the optical signal of QDs to bacteria is used for qualitative and quantitative analysis.
Yang et al. first used carboxyl-functionalized graphene QDs (CF GQDs) as fluorescent markers for optical imaging and sensing of E. coli O157: H7. They covalently combined E. coli O157: H7 antibodies with water-soluble CF GQDs to obtain CF GQDs immunofluorescent probes, which can improve the specificity of detection. The biosensor can produce an intense fluorescent signal with a minimum detection limit of 100 CFU/mL.
Fig.1 The schematic diagram of the preparation of immunofluorescence probe and pathogen detection. (Yang et al., 2018)
Fluorescence Imaging
Wang et al. reported a novel lipid-coated upconversion nanoparticle consisting of an upconversion nanocrystal core and a targeted lipid polymer shell for simultaneous NIR-triggered photodynamic therapy and cellular imaging. The UCN core acts as a transducer to convert deep penetrating NIR light to visible light for simultaneous activation of photosensitizers and cellular fluorescence imaging. The amphiphilic lipid polymer RGD peptide conjugated poly(maleic anhydride-1-octadecene) grafted with dioleoyl l-α-phosphatidylethanolamine (RGD-PMAO-DOPE) acts as a shielding agent. It protects the system from being caught by RES and locks the entire system at the site of the lesion. Drug loading can reach 9%. After NIR irradiation, MC540 is activated and successfully generates singlet state oxygen (ROS) through upconversion fluorescence emitted by UCN. Furthermore, UCN/RGD-PMAO-DOPE nanoparticles loaded with MC540 showed significant inhibitory effects on tumor cells after NIR irradiation. The data suggest that MC540-loaded UCN/RGD-PMAO-DOPE nanoparticles may be a useful nanoplatform for future PDT treatment of deep-seated cancers.
Fig. 2 Scheme of lipid coated unconverting nanoparticles getting into cells for NIR triggered photodynamic therapy and cell imaging simultaneously. (Wang et al., 2014)
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
- Yang, et al. Preparation of the Cf-GQDs-Escherichia coli O157: H7 Bioprobe and Its Application in Optical Imaging and Sensing of Escherichia coli O157: H7[J]. Food Analytical Methods, 2018.
- Wang, Hanjie , et al. Lipid coated upconverting nanoparticles as NIR remote controlled transducer for simultaneous photodynamic therapy and cell imaging[J]. International Journal of Pharmaceutics, 2014, 466(1-2):307-313.
* It should be noted that our service is only used for research, not for clinical use.
