Highly fluorescent dye-doped silica nanoparticles increase flow cytometry sensitivity for cancer cell monitoring
Silica nanoparticle, ﬂow cytometry, aptamer, cell detection, polyethylene glycol, ﬂuorophore
Early and accurate diagnosis and treatment of cancer depend on rapid, sensitive, and selective detection of tumor cells. Current diagnosis of cancers, especially leukemia, relies on histology and ﬂ ow cytometry using single dye-labeled antibodies. However, this combination may not lead to high signal output, which can hinder detection, especially when the probes have relatively weak afﬁ nities or when the receptor is expressed in a low concentration on the target cell surface. To solve these problems, we have developed a novel method for sensitive and rapid detection of cancer cells using dye-doped silica nanoparticles (NPs) which increases detection sensitivity in ﬂ ow cytometry analyses between 10- and 100-fold compared to standard methods. Our NPs are ~60 nm in size and can encapsulate thousands of individual dye molecules within their matrix. We have extensively investigated surface modiﬁ cation strategies in order to make the NPs suitable for selective detection of cancer cells using ﬂ ow cytometry. The NPs are functionalized with polyethylene glycol (PEG) to prevent nonspeciﬁ c interactions and with neutravidin to allow universal binding with biotinylated molecules. By virtue of their reliable and selective detection of target cancer cells, these NPs have demonstrated their promising usefulness in conventional ﬂ ow cytometry. Moreover, they have shown low background signal, high signal enhancement, and efﬁ cient functionalization, either with antibody- or aptamer-targeting moieties.
Tsinghua University Press
M. -Carmen Estévez,Meghan B. O’Donoghue,Xiaolan Chen,Weihong Tan, Highly fluorescent dye-doped silica nanoparticles increase flow cytometry sensitivity for cancer cell monitoring. NanoRes.2009, 2: 448-461