Mechanochemical Delivery and Dynamic Tracking of Fluorescent Quantum Dots in the Cytoplasm and Nucleus of Living Cells

Department of Mechanical Science and Engineering, University of Illinois at Urbana-Champaign, 1206 West Green Street, Urbana, Illinois 61801, USA.
Nano Letters (Impact Factor: 13.59). 05/2009; 9(5):2193-8. DOI: 10.1021/nl901047u
Source: PubMed


Studying molecular dynamics inside living cells is a major but highly rewarding challenge in cell biology. We present a nanoscale mechanochemical method to deliver fluorescent quantum dots (QDs) into living cells, using a membrane-penetrating nanoneedle. We demonstrate the selective delivery of monodispersed QDs into the cytoplasm and the nucleus of living cells and the tracking of the delivered QDs inside the cells. The ability to deliver and track QDs may invite unconventional strategies for studying biological processes and biophysical properties in living cells with spatial and temporal precision, potentially with molecular resolution.

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    • "The physical properties of culture substrates are found to widely affect the phenotypes and gene expression of a number of normal and cancerous cells [1], [17], [18], [35], [36], [37], [38], [39], [40], [41], [42], [43], [44], [45], [46], [47], [48], [49], [50], [51], [52], [53], [54], [55]. To respond to substrate stimuli, cells adhere to and spread on the substrate followed by sensing and processing both mechanical and chemical signals [26], [37], [44], [46], [49], [53], [55], [56], [57], [58], [59], [60], [61]. As we have previously shown [1], after 7-day culture on soft substrates, HCT-8 cells undergo an E to R transition characterized by R cells dissociating from the parent epithelial cell layer or cell islands. "
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