Multifunctional nanobioprobes detect and isolate multiple types of cancer cells

(Nanowerk Spotlight) Multifunctional nanomaterials have become widely researched in nanomedicine with the goal of developing highly accurate probes for detecting and isolating cancer cells. Of particular interest here are magnetic nanoparticles, which offer the capability of cell isolation from original or enriched samples without the use of centrifugation or filtration. In particular, the combination of fluorescent quantum dots and magnetic nanoparticles into single nanospheres to obtain fluorescent-magnetic bifunctional nanospheres has created the potential for broader applications in biomedicine and in clinical diagnosis (see for instance "Visual Recognition and Efficient Isolation of Apoptotic Cells with Fluorescent-Magnetic-Biotargeting Multifunctional Nanospheres").

In new work, researchers in China have now expanded this technique to multiplexed assays. They demonstrated the ability to detect and collect multiple types of cancer cells, such as leukemia cells and prostate cancer cells, from mixed samples within 25 minutes by using a magnet and an ordinary fluorescence microscope.

"Building on years of work, we have now demonstrated that we can successfully detect and extract tumour cells from complex samples containing both normal cells and the target cancer cells," Dai-Wen Pang, Luojia Professor of Chemistry and Director of the Research Center for Nanobiology and Nanomedicine at Wuhan University, tells Nanowerk. "Compared to our previously published work, we used a system of multiple types of rare target cancer cells at concentrations as low as 0.01% in mixed cell samples as a model to demonstrate that our multifunctional nanobioprobe-based analytical method could meet the need for a simple, fast, low-cost, and highly sensitive multi-component assay."

Schematic drawing of the recognition of specific cancer cells by nanobioprobes. (A) Two types of nanobioprobes coated with anti-CD3 or anti-PSMA mAb recognize Jurkat T cells or LNCaP cells, respectively. (B) Magnetic isolation of cancer cells bound by nanobioprobes. (C) Fluorescent imaging of target cancer cells under a fluorescence microscope. When a mixture of the two types of cancer cells in A was bound by their respective nanobioprobes, they can be distinguished under UV due to different colors of the attached nanobioprobes. (Reprinted with permission from American Chemical Society)

The team reports its findings in the January 20, 2011 online edition of ACS Nano ("Fluorescent-Magnetic-Biotargeting Multifunctional Nanobioprobes for Detecting and Isolating Multiple Types of Tumor Cells").