McCormick School of Engineering, Northwestern University

Monica Olvera de la Cruz

Lawyer Taylor Professor of Materials Science and Engineering, Chemistry and (by courtesy) Chemical and Biological Engineering

Director, Materials Research Science and Engineering (MRSEC)

Education

Ph.D. Physics, Cambridge University, Cambridge, England

B.A. Physics, Universidad Nacional Autonoma de Mexico (UNAM), Mexico City, Mexico

Research Interests

Multicomponent mixtures of complex molecules have competing interactions of different length scales which can be used to design a large variety of assemblies with important technological and biomedical applications. Oppositely charged biomolecules, such as polynucleotides and proteins, for example, co-assemble into functional units including nucleosomes and viruses at specific ionic concentrations. The driving force for association of oppositely charged macroions is counterion release and strong ionic correlations upon association.

We analyze co-assemblies of cationic and anionic biological and synthetic molecules and their stability in different ionic media by using a combination of liquid theory and solid state physics techniques. The association of chemically incompatible charged molecules often results in surface charge heterogeneities which lead to hierarchical organizations via charge polarizability. Surface composition heterogeneities are a result of the competition of electrostatic interactions, which favor mixing of opposite charges, and specific interactions and packing constraints which favor segregation of the components.

We analyze the physical properties of mixtures of cationic and anionic amphiphiles co-assembled into lipid membranes, vesicles and cylindrical micelles. We also analyze surface patterns induced by the adsorption or confinement of self-attracting charged biomolecules onto oppositely charged flat and curved surfaces, such as cationic proteins onto actin, and determine the attraction mechanism among surfaces with charge heterogeneities.

We also investigate the thermodynamics, statistics and dynamics of multicomponent mixtures of neutral molecues. In particular, we analyze immiscible molecular fluids including interface adsorption of minority components and phase segregation kinetics. In solutions containing copolymers, for example, the interface adsorption is enhanced and a large variety of structures with unique applications including inverted micelles for drug delivery are obtained.

Significant Recognition

• National Institutes of Health FIRST Award, 1988–93
• David and Lucille Packard Fellowship for Science and Engineering, 1989–94
• Alfred P. Sloan Fellowship, 1990–92
• NSF Presidential Young Investigator Award, 1990–95
• Fellow of the American Physical Society, 2001
• Engineering and Applied Sciences Cozzarelli Prize, Proceeding of the National Academies, National Academies, 2007
• 2010 American Academy of Arts and Sciences Fellow
• 2010-2015 National Security Science and Engineering Faculty Fellowship
• 2012 Elected member of the National Academy of Sciences
• 2013 Distinguished Lecturer, Mathematical Physical Sciences Directorate, National Science Foundation

Significant Professional Service

• Scientific Member, Commissariat a l’Énergie Atomique (CE-SACLAY), 1995-97
• NSF Opportunities in Materials Theory, speaker, 2000
• Scientific Visitor, Service de Physique Théorique, CE-SACLAY, France, 2003
• NSF Role of Theory in Biological Physics and Materials, organizer & speaker, 2004
• Baetjer Lecturer, Princeton University, 2005
• Editorial Board of the Journal of Polymer Science B: Polymer Physics, 2000-06
• Advisory Committee, NSF Mathematical and Physical Sciences Directorate, 2005-09
• Solid State Science Committee, National Research Council, 2006-09
• Research at the Intersection of Physical and Life Sciences Committee, National Research Council, National Academies, 2007-09
• Editorial Board of Macromolecules
• Vice-chair Solid Sate Science Committee, National Research Council, 2008-10
• Chair, Advisory Committee, NSF Division of Materials Research, 2007-09
• Member, National Research Council Board of Physics and Astronomy
• Chair, Condensed Matter and Materials Research Committee, National Research Council, 2010-12
• Basic Energy Sciences Advisory Committee, Department of Energy, 2013-2015

Selected Publications

• Nap, R. J.; Szleifer, I.; de la Cruz, M. O.; Popov, K. I., “Interacting nanoparticles with functional surface groups”, Journal of Polymer Science Part B: Polymer Physics, (2012)
• Jha, P. K.; Olvera de la Cruz, M.; Wu, K. A., “Pattern Selection in Polyelectrolyte Gels by Nonlinear Elasticity”, Macromolecules, (2012)
• T. I. N. G. Li, R. Sknepnek, R. J. Macfarlane, C. A. Mirkin and M. O. de la Cruz, “Modeling the Crystallization of Spherical Nucleic Acid Nanoparticle Conjugates with Molecular Dynamics Simulations”, Nano Letters, (2012)
• M. F. Demers, R. Sknepnek and M. O. de la Cruz, “Curvature-driven effective attraction in multicomponent membranes”, Physical Review E, (2012)
• S. Dhakal, F. J. Solis and M. O. de la Cruz, “Nematic liquid crystals on spherical surfaces: Control of defect configurations by temperature, density, and rod shape”, Physical Review E, (2012)
• R. Sknepnek and M. O. de la Cruz, “Nonlinear elastic model for faceting of vesicles with soft grain boundaries”, Physical Review E, (2012)
• de la Cruz, M. O.; Su, J.; Guo, H., “Solubility and transport of cationic and anionic patterned nanoparticles”, Physical Review E, (2012)
• Szleifer, I.; de la Cruz, M. O.; Longo, G. S., “Molecular theory of weak polyelectrolyte thin films”, Soft Matter, (2012)