Jason McNeill
Assistant Professor
Physical Chemistry
Phone: (864) 656-4065
Office: 365 Hunter Laboratories
E-mail: mcneill@clemson.edu
Research Interests | Publications | Research Group
Dr. McNeill earned a B.S. in Chemistry (1991) from Northern Illinois University and a Ph.D. (1999) from the University of California at Berkeley. He conducted postdoctoral research at the University of Texas at Austin. In 2006 he received the CAREER Award from the National Science Foundation.
Research Interests
Fluorescent “Polymer Dot” Nanoparticles
We are currently developing novel probes for advanced fluorescence applications based on nanoparticles consisting of one or more conjugated polymer molecules. These “polymer dot” nanoparticles can be prepared in sizes ranging from ~3 nm in diameter (single polymer molecules) to ~100 nm in diameter. These nanoparticles possess unique optical properties that have a number of possible applications such as nanoparticle-based biomolecule sensors and tracking of individual molecules inside live cells. Initial results obtained using single molecule spectroscopy methods indicate that conjugated polymers are 100X brighter than conventional fluorescent probes. The nanoparticles also exhibit highly efficient energy transfer—in the presence of metal nanoparticles, the polymer dot fluorescence is efficiently quenched by energy transfer to metal nanoparticles. We are currently developing a number of sensor architectures that take advantage of the extraordinarily high brightness and energy transfer characteristics of these nanoparticles.
Left: Photo of various polymer dot nanoparticles suspended in water, under UV excitation. Right: AFM of polymer dot nanoparticles dispersed on a mica substrate.
Intracellular Single Molecule Dynamics
Our development of ultra-bright nanoparticles has made it possible to detect the fluorescence of isolated nanoparticles 5-10 nm in diameter inside a living cell. We are currently developing methods for tracking individual biomolecules or virus particles in the intracellular environment with unprecedented precision. The high brightness, relatively small size, and excellent photostability of the nanoparticles are ideal for either short or long-term tracking of biomolecules with subwavelength precision inside living cells, where autofluorescence and scattering effects typically drown out the fluorescence signal of individual dyes and nanoparticles, rendering single molecule tracking difficult or impossible.
Left: Multiphoton-excited fluorescence image of single conjugated polymer nanoparticles. Right: Fluorescence image of macrophage cells loaded with ~5-10 nanoparticles per cell, overlaid with DIC image.
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Publications
1. C. Szymanski, C. Wu, J. Hooper, M. A. Salazar, A. Perdomo, A. Dukes, and J. D. McNeill, “Single Molecule Nanoparticles of the Conjugated Polymer MEH-PPV, Preparation and Characterization by Near-Field Scanning Optical Microscopy,” Journal of Physical Chemistry B, 109, 8543 (2005).
2. C. Wu, H. Peng, Y. Jiang, and J. McNeill, “Energy Transfer Mediated Fluorescence from Blended Conjugated Polymer Nanoparticles,” Journal of Physical Chemistry B, 110, 14148 (2006).
3. C. Wu, C. Szymanski, and J. McNeill, “Preparation and encapsulation of highly fluorescent conjugated polymer nanoparticles,” Langmuir, 22, 2956 (2006).
4. C. Wu, H. Peng, and J. D. McNeill, “Highly Fluorescent Europium Chelate Nanoparticles,” Langmuir, 23, 1591 (2007).
5. C. Wu, C. Szymanski, Z. Cain, and J. D. McNeill, “Conjugated Polymer Dots for Multiphoton Fluorescence Imaging,” Journal of the American Chemical Society, 129, 12904 (2007).
6. C. Wu, Y. Zheng, C. Szymanski, C. Daniel, and J. D. McNeill, “Energy Transfer in a Nanoscale Multichromophoric System: Dye Doped Conjugated Polymer Nanoparticles,” Journal of Physical Chemistry C, 112, 1772 (2008).
7. C. Wu and J. McNeill, “Swelling-controlled polymer phase and fluorescence properties of polyfluorene nanoparticles,” Langmuir, 24, 5855 (2008).
8. C. Wu, B. Bull, C. Szymanski, K. Christensen, and J. McNeill, “Multicolor Conjugated Polymer Dots for Single Molecule Fluorescence Detection in Living Cells,” ACS Nano, 2, 2415 (2008).
9. C. Wu, B. Bull, K. Christensen, and J. McNeill, “Ratiometric Single Nanoparticle Oxygen Sensors for Biological Imaging,” Angew. Chemie Intl. Ed., 48, 2741 (2009).
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