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Updated: Feb 9, 2026

Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping
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Silicon Metal-oxide-semiconductor Quantum Dots for Single-electron Pumping

Published on: June 3, 2015

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Detection of CD22 Expression in Living Cancer Cells by Semiconductor Quantum Dots

Meijiao Zhang, Shizhu Zang, Guangbo Ge

    Journal of Biomedical Nanotechnology
    |June 16, 2018
    PubMed

    Insights

    Researchers developed N-acetylneuraminic acid quantum dots (NANA-QDs) for precise CD22 targeting and fluorescence imaging. This novel nanoprobe shows promise for diagnosing autoimmune diseases and B cell malignancies.

    Area of Science:

    • Biomedical Engineering
    • Nanotechnology
    • Cell Biology

    Background:

    • CD22 is a key target for treating autoimmune diseases and B cell cancers.
    • Developing effective imaging agents for CD22 is crucial for diagnosis and therapy.

    Purpose of the Study:

    • To synthesize and characterize N-acetylneuraminic acid functionalized quantum dots (NANA-QDs) for CD22 targeting.
    • To evaluate the specificity and efficacy of NANA-QDs for fluorescence imaging of CD22 on living cells.

    Main Methods:

    • Conjugation of N-acetylneuraminic acid (NANA) to carboxyl-modified CdSe/ZnS quantum dots (COOH-QDs).
    • Characterization of NANA-QDs for size, cytotoxicity, and fluorescence properties.
    • Validation of CD22 targeting using cellular uptake inhibition, colocalization studies, and endocytosis assays.
    • Quantification of CD22 expression levels in cancer cells using the NANA-QDs assay.

    Main Results:

    • NANA-QDs exhibited excellent size distribution, low cytotoxicity, and strong fluorescence.
    • The nanoprobe specifically targeted CD22 on living cancer cells, confirmed by colocalization and uptake studies.
    • The NANA-QDs assay accurately determined CD22 expression levels, consistent with immunofluorescence and western blotting.

    Conclusions:

    • NANA-QDs represent a practical and effective fluorescent nanoprobe for CD22 bioimaging.
    • This system holds significant potential for biomedical applications related to CD22 in autoimmune diseases and malignancies.

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