Catherine J. Murphy / Faculty / Chemistry at Illinois

Professor Murphy received two B.S. degrees, one in chemistry and one in biochemistry, from the University of Illinois in 1986. She received her Ph.D. from the University of Wisconsin in 1990. From 1990-1993, she was first an NSF and then an NIH postdoctoral fellow at the California Institute of Technology. From 1993-2009 Professor Murphy was a faculty member in the Department of Chemistry and Biochemistry at the University of South Carolina. In August 2009 she joined the faculty of the Department of Chemistry at the University of Illinois.

Research

Our research is at the interface of materials chemistry, inorganic chemistry, biophysical chemistry and nanotechnology. Our primary goal is to develop inorganic nanomaterials for biological and energy-related applications, and understand the chemical interactions of these nanomaterials with their surroundings. A diverse range of projects are currently pursued in the group:

Inorganic Nanoparticle Fabrication and Functionalization.

"Finely-divided metals" such as gold, silver and copper have been known since Roman times for their brilliant colors. These brilliant colors arise fundamentally from the interaction of light with the conduction band electrons in these nanoscale metal particles, producing what is known as a plasmon resonance at particular optical frequencies. Nanorods, compared to nanospheres, have multiple plasmon bands whose position and intensity are intimately connected to the size, shape, degree of aggregation, and local dielectric environment of the nanorods. The absorption and scattering of light by gold and silver nanorods can be tuned throughout the visible and near-infrared portions of the electromagnetic spectrum. We have developed a set of synthetic approaches to fabricate gold and silver nanorods of controlled size and shape in high yields. Molecules can be placed on the nanorod surface using covalent attachment chemistries or polyelectrolyte layer-by-layer adsorption to position them at desired distances, and possibly orientations, from the nanoscale metal surface. On-particle reactions are being explored to improve the compatibility and ease of processing of these materials.

Cellular Imaging, Chemical Sensing, and Photothermal Therapy Using Gold Nanorods.

The strong plasmon bands of noble metal nanoparticles make them ideal for biological sensing and imaging applications. We have used the elastic light scattering properties of gold nanorods as "nano strain gauges" to measure the deformation of soft matrices by living cells. The inelastic light scattering (Raman) properties of gold nanorods can be used to interrogate the local chemical environment of the nanorods. Irradiation into nanorod plasmon bands causes large temperature jumps in the local environment, which we have exploited as a way to kill multidrug-resistant bacteria (once the nanorods are surface-modified to recognize the bacteria).

Environmental Implications of Nanoparticles.

How are nanoparticles distributed and modified in complex biological systems? Can nanoparticles sequester or deliver small molecules across interfaces? How do these processes depend, if at all, on nanoparticle size, shape, aggregation state, and surface chemistry? These are questions that we seek to address using a battery of analytical, physical, and biochemical techniques.

Publications

Khnayzer, R. S.; Zamkov, M.; Thompson, L. B.; Murphy, C. J.; Castellano, F. N. "Heterogeneous Photocatalytic Hydrogen Production at Titania Derived from Surface-Anchored Molecular Precursors", J. Phys. Chem. C 2012, 116, 1429-1438.

Murph, S. E. H.; Murphy, C. J.; Colon-Mercado, H. R.; Torres, R. D.; Heroux, K. J.; Thompson, L. B.; Haasch, R. T. "Tuning the Size and Shape of Au-Pt Nanocatalyst for Direct Methanol Fuel Cells", J. Nanopart. Res. 2011, 13, 6347-6364.

Murphy, C. J.; Thompson, L. B.; Chernak, D. J.; Yang, J. A.; Sivapalan, S. T.; Boulos, S. P.; Huang, J.; Alkilany, A. M.; Sisco, P. N. "Gold Nanorod Crystal Growth: From Seed-Mediated Synthesis to Nanoscale Sculpting", Curr. Opin. Colloid. Interfac. Sci. 2011, 16, 128-134.

Zill, A.; Rutz, A. L.; Kohman, R. E.; Alkilany, A. M.; Murphy, C. J.; Kong, H.; Zimmerman, S. C. "Clickable Polyglycerol Hyperbranched Polymers and Their Application to Gold Nanoparticles and Acid-Labile Nanocarriers," Chem Commun 2011, 47, 1279-1281.

Alkilany, A. M.; Thompson, L. B.; Murphy, C. J. "Polyelectrolyte Coating Provides a Facile Route to Suspend Gold Nanorods in Polar Organic Solvents and Hydrophobic Polymers," ACS Appl. Mater. & Interfac. 2010, 2, 3417-3421.

Murphy, C. J.; Thompson, L. B.; Alkilany, A. M.; Sisco, P. N.; Boulos, S. P.; Sivapalan, S.; Yang, J. A.; Chernak, D. J.; Huang, J. "The Many Faces of Gold Nanorods," J. Phys. Chem. Lett. 2010, 1, 2867-2875.

Alkilany, A. M.; Murphy, C. J. "Toxicity and Cellular Uptake of Gold Nanoparticles: What Have We Learned So Far?" J. Nanopart. Res. 2010, 12, 2313-2333.

Alkilany, A. M.; Nagaria, P. K.; Wyatt, M. D.; Murphy, C. J. "Cation Exchange on the Surface of Gold Nanorods with a Polymerizable Surfactant: Polymerization, Stability, and Toxicity Evaluation," Langmuir 2010, 26, 9328-9333.

Wilson, C. G.; Sisco, P. N.; Gadala-Maria, F. A.; Murphy, C. J.; Goldsmith, E. C. "Polyelectrolyte-Coated Gold Nanorods and Their Interactions with Type I Collagen," Biomaterials 2009, 30, 5639-5648.

Ferry, J. L.; Craig, P; Hexel, C.; Sisco, P. N.; Frey, R.; Pennington, P; Fulton, M.; Scott, G.; Decho, A.; Kashiwada, S.; Murphy, C. J.; Shaw, T. J. "Transfer of Gold Nanoparticles from the Water Column to the Estuarine Food Web," Nature Nanotechnology 2009, 4, 441-444.

Murphy, C. J. "Spatial Control of Chemistry on the Inside and Outside of Inorganic Nanocrystals," ACS Nano 2009, 4, 770-774.

Sisco, P. N.; Murphy, C. J. "Surface Coverage Dependence of Surface-Enhanced Raman Scattering from Gold Nanocubes on Self-Assembled Monolayers of Analyte," J. Phys. Chem. A, 2009, 113, 3973-3978.

Alkilany, A. M.; Nagaria, P.; Hexel, C. R.; Shaw, T. J.; Murphy, C. J.; Wyatt, M. D. "Cellular Uptake and Cytotoxicity of Gold Nanorods: Molecular Origin of Cytotoxicity and Surface Effects," Small 2009, 5, 701-708.

Gole, A.; Agarwal, N.; Nagaria, P.; Wyatt, M. D.; Murphy, C. J. "One-Pot Synthesis of Silica-Coated Magnetic Plasmonic Tracer Nanoparticles," Chem. Commun. 2008, 6140-6142.

Murphy, C. J.; Gole, A. M.; Stone, J. W.; Sisco, P. N.; Alkilany, A. M.; Goldsmith, E. C.; Baxter, S. C. "Gold Nanoparticles in Biology: Beyond Toxicity to Cellular Imaging," Acc. Chem. Res. 2008, 41, 1721-1730.

Sisco, P. N.; Minrova, E.; Wilson, C.; Murphy, C. J.; Goldsmith, E. C. "The Effect of Gold Nanorods on Cell-Mediated Collagen Remodeling," NanoLetters 2008, 8, 3409-3412.

Alkilany, A. M.; Frey, R. L.; Ferry, J. L.; Murphy, C. J. "Gold Nanorods as Nanoadmicelles: 1-Naphthol Partitioning into a Nanorod-Bound Surfactant Bilayer," Langmuir 2008, 24, 10235-10239.

Norman, R. S.; Stone, J. W.; Gole, A.; Murphy, C. J.; Sabo-Attwood, T. "Photothermal Destruction of the Bacterium Pseudomonas Ariginosa by Gold Nanorods," NanoLetters 2008, 8, 302-306.

Berg, M. A.; Coleman, R. S.; Murphy, C. J. "Nanoscale Structure and Dynamics of DNA," PhysChemChemPhys 2008, 10, 1229-1242.

Gole, A.; Murphy, C. J. "Azide-Derivatized Gold Nanorods: Functional Materials for 'Click' Chemistry," Langmuir 2008, 24, 266-272.

Awards

2011 Fellow of the American Chemical Society
2011 Lucy W. Pickett Lecturer, Mount Holyoke College
2011 Inorganic Nanoscience Award, given by the Division of Inorganic Chemistry, American Chemical Society
AAAS Fellow, 2008
USC Russell Award for Research in Science, Mathematics, and Engineering, 2005.
Outstanding Undergraduate Research Mentor Award, University of South Carolina, 2003
Michael J. Mungo Award for Excellence in Undergraduate Teaching, University of South Carolina, 2001
Golden Key Faculty Award for the Integration of Research and Undergraduate Teaching, 1998
Camille Dreyfus Teacher-Scholar Award, 1998-2000
Alfred P. Sloan Foundation Research Fellow, 1997-1999
Cottrell Scholar Award, 1996-2001
National Science Foundation CAREER Award, 1995-1998

Highlights

Catherine J. Murphy named #32 in Science Watch's "Top Chemists of the Decade, 2000-2010"

Catherine J. Murphy named #10 in Science Watch's "Top Materials Scientists of the Decade, 2000-2010"

Top Five ACS article by citations, National Chemistry Week, 2007: Murphy, C. J.; Sau, T. K.; Gole, A.; Orendorff, C. J.; Gao, J.; Gou, L.; Hunyadi, S. Li, T. "Anisotropic Metal Nanoparticles: Synthesis, Assembly, and Optical Applications", J. Phys. Chem. B 2005, 109, 13857-13870.