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Nanocrystal-Based Biomimetic System for Quantitative Flow Cytometry



Marina Dobrovolskaia, Hyeong G. Kang, Matthew L. Clarke, Anil Patri, Jeeseong Hwang


Flow cytometry has been instrumental in rapid analysis of single cells since the 1970s. One of the common approaches is the immunofluorescence study involving labeling of cells with antibodies conjugated to organic fluorophores. More recently, as the application of flow cytometry extended from simple cell detection to single-cell proteomic analysis, the need of determining the actual number of antigens in a single cell has driven the flow cytomery technique towards a quantitative methodology. However, organic fluorophores are challenging to use as probes for quantitative detection due to the lack of photostability and of quantitative fluorescence standards. NIST provides a set of fluorescein isothiocyanate (FITC) labeled beads, RM 8640, which is the only nationally recognized fluorescent particle standard. On the other hand, optical characteristics of semiconductor quantum dots or nanocrystals (NCs) are superior to traditional dye molecules for the use as tags for biological and chemical fluorescent sensors and detectors. Compelling advantages of NCs include long photostability, broad spectral coverage, easy excitation, and suitability for multiplexed sensing. Recently, novel surface coatings have been developed to render NCs water soluble and bio-conjugation ready, leading to their use as fluorescent tags and sensors for a variety of biological applications including immunolabeling of cells. Here, we describe our approach of using fluorescent semiconductor NCs as a novel tool for quantitative flow cytometry detection tool. Our strategy involves the development of immuno-labeled NC-conjugated silica beads as biomimetic cells. In addition to flow cytometry, the NC-conjugated silica beads were characterized by electron and fluorescence
Proceedings Title
Proceedings of the SPIE | 2007 | SPIE
Conference Dates
January 23-24, 2007
Conference Title
SPIE Proceedings


bio-conjugation, biomimetic cell, flow cytometry, fluorescence standard, nanocrystal, quantum dot


Dobrovolskaia, M. , Kang, H. , Clarke, M. , Patri, A. and Hwang, J. (2007), Nanocrystal-Based Biomimetic System for Quantitative Flow Cytometry, Proceedings of the SPIE | 2007 | SPIE (Accessed April 23, 2024)
Created February 6, 2007, Updated January 27, 2020