Perovskite Quantum Dots Supplier - Alfa Chemistry

Anti-human CD3 Conjugated Cd Quantum Dots

Product Description

Alfa Chemistry can provide customers with anti-human CD3 conjugated Cd quantum dots in the emission spectral range from 525 nm to 665 nm, with excellent chemical and optical stability, good quality stability and high quantum yield.


Fluorescent Probes

The study by Hsieh et al. presents an efficient and sensitive method for detecting rare cells without cell culture, in which quantitative analysis of cells is performed using quantum dots (QDs) as fluorescent probes. Through the binding of QDs to cells, the biotin-streptavidin reaction acts as a bridge connecting QDs and cells. Cells can be quantified based on the correlation between the fluorescence intensity of QDs and the number of cells. Non-specific adsorption and cross-reactivity of QD625-streptavidin on T-cell membranes are neglected by reacting with biotin anti-human CD3 and by mixing with erythrocytes, respectively. The photoactivation cycle and pH can be controlled to increase the fluorescence of the cell population, which increases linearly with the number of T cells from 40 to 100,000, not only in single T cell lines but also when mixed with a total of 106 erythrocytes. In addition, specific T cells can be detected within 15 minutes, even though the rare specific cell count may be only 40 cells. Among these advantages, the proposed system for detecting rare cells includes simple preparation, low cost, rapid detection and high sensitivity, all of which could facilitate the detection of circulating tumor cells in the early stages of diagnosis or prognosis.

Fig.1 Principle of T cell coupling with quantum dots as fluorescence marker. (Hsieh et al., 2010)Fig.1 Principle of T cell coupling with quantum dots as fluorescence marker. (Hsieh et al., 2010)

Cancer Cell Detection

A rapid and sensitive method for detecting cancer cells at low concentrations was proposed by Hsieh et al. In this method, two biomarkers of T-help cancer cells are detected simultaneously. One biomarker is combined with magnetic beads to separate T-help cells from the mixture, and the other biomarker is associated with quantum dots for detecting fluorescence. Specific T-help cells can be quantified using the relationship between QD fluorescence intensity and cell frequency after magnetic separation. Fluorescence intensity increases linearly with the frequency of T-helper cells from 10-7 to 10-3, and neither B cells nor red blood cells interfere with the detection of T-helper cells. In addition, the total detection time was under 15 min even for specific T-helper cells at frequencies as low as 5 × 10-7. The numerous advantages of using the proposed method to detect specific cells at low concentrations include ease of preparation, low cost, fast detection and high sensitivity.

Fig. 2 Principle of detecting the specific T-help cells using combination of two biomarkers with quantum dots. (Hsieh et al., 2011)Fig. 2 Principle of detecting the specific T-help cells using combination of two biomarkers with quantum dots. (Hsieh et al., 2011)

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.


  1. Hsieh, Yi-Heui, et al. Highly sensitive rare cell detection based on quantum dot probe fluorescence analysis[J]. Analytical and bioanalytical chemistry, 2010, 396(3): 1135-1141.
  2. Hsieh, Y. H. , et al. Rapid and sensitive detection of cancer cells by coupling with quantum dots and immunomagnetic separation at low concentrations[J]. Biosensors & Bioelectronics, 2011, 26(10):4249-4252.
* It should be noted that our service is only used for research, not for clinical use.


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