About

Monica Olvera de la Cruz is the Lawyer Taylor Professor of Materials Science and Engineering, Chemistry, and (by courtesy) Chemical and Biological Engineering, Physics and Astronomy at Northwestern University. She serves as the Director of the Center for Computation & Theory of Soft Materials and the Deputy Director of the Center for Bio-Inspired Energy Science. Her research group focuses on the design and control of materials responsive to external stimuli, developing models to describe the structure and function of assemblies of heterogeneous molecules including amphiphiles, copolymers, and both synthetic and biological polyelectrolytes, as well as multicomponent complex fluids. Her work has led to significant advances in understanding ionic-driven assembly, electrostatic spontaneous symmetry breaking of ionic fibers and membranes, and their relevance to biological functions and the development of functional materials. Her investigations in soft and condensed matter physics have contributed to scientific knowledge and opened new research fields of technological importance, such as gel electrophoresis dynamics, self-organization of molecular electrolytes into bio-mimetic materials, and the self-assembly of heterogeneous molecules into complex nanostructures. Recognized with numerous awards and honors, including election to the National Academy of Sciences and membership in the American Philosophical Society, she is a prominent figure in her field with extensive professional service at national and international levels.

Research topics

• Chemistry
• Materials science
• Nanotechnology
• Organic chemistry
• Chemical engineering
• Artificial Intelligence
• Biochemistry
• Computer Science
• Physical chemistry
• Crystallography
• Biophysics
• Environmental chemistry
• Chemical physics
• Physics
• Biology
• Cell biology
• Polymer chemistry

Selected publications

• Electrostatically driven pattern formation in mixed charged–neutral multicomponent elastic membranes

  Proceedings of the National Academy of Sciences · 2026-03-10

  articleOpen accessSenior authorCorresponding

  Multicomponent crystalline and amorphous elastic shells exhibit heterogeneous surface patterns that provide distinctive functionalities in cellular environments. Such patterning typically arises from the competition between short-range attractive and long-range repulsive interactions in membranes. Here, we demonstrate that the intrinsic competition between electrostatic repulsion and elastic deformation is sufficient to drive spontaneous surface patterning in elastic shells, requiring no additional attractive interactions. Using numerical simulations, we demonstrate pattern formation in mechanically homogeneous membranes with heterogeneous surface charge composition across different topologies, including spheres, discs, and flat periodic membranes. We also examine patterns in crystalline and amorphous shells of coassembled charged and neutral components with different bending rigidities. At low charge fraction, discrete charged surface domains form. At intermediate charge fraction, the competition between electrostatics and elasticity leads to elongated domains (rods) of the charged component, which results in lamellar patterns at nearly equal fraction of the charged and neutral components. At high charge fraction, nanodomains of the neutral component form. Amorphous shells exhibit similar progressions but with disordered structures rather than ordered lamellar patterns. These pattern morphologies are observed in both the closed shells and flat membranes. As salt concentration increases, all patterns coarsen due to the screening of electrostatic interactions.

  PublisherDOI

• Engineering the Self-assembly of Bacterial Microcompartment Shell Proteins via Charged Mutations

  bioRxiv (Cold Spring Harbor Laboratory) · 2026-01-30

  articleOpen accessSenior authorCorresponding

  Abstract Protein self-assembly is a fundamental biological process of great importance for the design and synthesis of biomaterials. Developing the ability to precisely manipulate protein assembly would greatly expand both our understanding of the process and our biotechnological capabilities. Within bacteria, proteins that self-organize to form bacterial microcompartments (MCPs) offer an excellent model system for studying protein self-assembly and advancing biomaterial design capabilities. MCPs consist of irregular polyhedral shells that encase an enzyme core, functioning as enzymatic nanoreactors. In isolation, the abundant shell proteins of the 1,2-propanediol utilization (Pdu) MCP, PduA and PduJ, have a high propensity to self-assemble into tubular structures, analogous in form to carbon nanotubes. Here, we design and characterize tubular structures formed by hexameric PduA and PduJ proteins. We demonstrate that altering hexamer charge offers a systematic strategy for modulating the higherorder assembly of PduA and PduJ across multiple contexts by integrating molecular dynamics simulations with heterologous overexpression, cell-free, and in vivo Salmonella enterica serovar Typhimurium LT2 experiments. First, using molecular simulation, we find that tube chirality and radius play critical roles in determining structural stability and flexibility. Next, overexpression and cell-free experiments show that increasing the overall negative charge of assembling subunits consistently promotes self-assembly into tubular structures. We find that this holds true in the native MCP system, as these same mutations promote the formation of tubular MCP structures in S. enterica LT2. Our results collectively reveal that both electrostatic interactions and fields generated by charges on proteins can be leveraged to control protein-based nanostructures.

  PublisherDOI

• Topologically Selective Deconstruction of Polymer Networks

  ChemRxiv · 2026-01-29

  articleOpen access

  Polymer network deconstruction is an essential process for biological systems and waste disposal, yet a thorough understanding of how polymer network structure, particularly topology, affects deconstruction is lacking. We report the discovery that esterase enzymes deconstruct polyester networks in a topologically selective manner, cleaving esters in primary loops substantially faster than compositionally identical esters in non-primary loop junctions. Mechanistic experiments and coarse-grained simulations indicate that preferential cleavage of primary-loop esters arises from reduced local and network-level steric crowding at primary-loop junctions. These findings establish polymer network topology as a general mode of control over polymer network deconstruction processes, with broad implications for (bio)materials remodeling and polyester recycling.

  PublisherOA PDFDOI

• Self-oscillating synchronematic colloids

  Nature Communications · 2026-01-23

  articleOpen accessCorresponding

  Self-oscillators that sustain periodic dynamics under constant input are ubiquitous in natural and engineered systems, where their interactions enable spatiotemporal coordination among many individual units. New forms of organization can emerge when these self-oscillating units are free to move and rotate, linking their spatial arrangement and orientation with their oscillation frequencies and phases. Here, we report experiments and simulations on populations of Quincke colloids that behave as self-oscillating units characterized by position, orientation, frequency, and phase. Hydrodynamic interactions among these colloids drive temporal synchronization and spatial alignment of their phases and orientations, giving rise to a new form of collective order that we term synchronematic. Within finite-size crystalline clusters, these non-reciprocal interactions promote global synchronization and circular alignment, with a collective frequency that increases with cluster size. Using the theory of weakly coupled oscillators, we derive a reduced-order model that captures the coupled evolution of phase and orientation and explains how synchronematic order depends sensitively on the particle configuration. Our results establish Quincke colloids as a model system for active oscillatory matter and reveal fundamental principles by which synchronization, alignment, and structure co-emerge—offering a framework for designing adaptive, frequency-tunable materials. Self-oscillators are critical in various natural and engineered systems, as they enable complex collective behaviors through interactions among individual units. This study demonstrates that populations of Quincke colloids-self-oscillators whose back-and-forth motion defines both a phase and a nematic oscillation axis-can achieve a form of collective order, termed synchronematic order, characterized by hydrodynamic interactions that synchronize their oscillation phases and align their orientations.

  PublisherDOI

• Unstructured protein mimics have enzymatic activity

  Chem · 2026-02-26

  articleSenior author
  PublisherDOI

• Role of Polymer–Protein Interactions in the Dynamics of Polymer-Integrated Protein Crystals

  Journal of the American Chemical Society · 2026-04-24

  article

  The incorporation of synthetic polymers into biomolecular materials provides a powerful strategy to enhance their properties. We recently showed that the interstitial spaces of highly solvated mesoporous ferritin crystals could be infiltrated with acrylate (Ac) and acrylamide (Am) monomers, which are subsequently polymerized in crystallo to yield a new class of hybrid materials termed Polymer-Integrated Protein Crystals (PIX). Our earlier studies had shown that ferritin-PIX displayed remarkable properties such as reversible expansion and contraction without losing crystalline order, efficient self-healing, and the ability to encapsulate and release large biomolecular cargo. However, the structure of the polyacrylate-co-acrylamide (p(Ac–Am)) polymer matrix, its distribution within the protein lattice, and the molecular nature of the protein–polymer interactions that ultimately engender the emergent properties of ferritin-PIX have remained unknown. Here, we combine small-angle neutron and X-ray scattering and analytical measurements with extensive all-atom and coarse-grained molecular dynamics simulations to examine the structure and dynamics of the polymer network within the crystalline framework of ferritin-PIX. Our results reveal an extensive and multivariate set of noncovalent interactions between the ferritin surfaces and p(Ac–Am) chains that sustain the structural coherence of the crystalline lattice while accommodating large-scale motions. Guided by these insights, we have demonstrated that changes in the chemical compositions of ferritin and the polymer matrix can be used to predictably control the structural dynamics of ferritin-PIX. Our increased molecular-level understanding and engineering of the polymer–protein interface in ferritin-PIX provide an important step toward the generalization of the PIX concept to other protein crystals and polymer compositions.

  PublisherDOI

• Chemo‐Mechanical Coupling in Hydrogels: Dynamics in the Diffusion‐Limited Regime

  Advanced Functional Materials · 2025-06-05 · 4 citations

  articleOpen accessSenior authorCorresponding

  Abstract Hydrogels are characterized by substantial volume changes in response to external stimuli, making them promising candidates for developing smart materials with enhanced adaptability and responsiveness. By integrating chemical reactions, hydrogels acquire dynamic and tunable responsiveness to external stimuli through chemo‐mechanical coupling, expanding their potential in emerging applications. However, capturing their transient behavior remains challenging due to the complex interplay of chemical reactions, solvent transport, and polymer network deformation. Classical theories capture equilibrium swelling but fail to describe time‐dependent phenomena. To address this, a time‐dependent continuum model is developed that explicitly couples these processes. Volume phase transition in hydrogels with homogeneous chemical reactions is investigated, then the effects of reaction kinetics on these transitions are analyzed. The coupling of these mechanisms is further explored through a study of transient mechanical instabilities. To illustrate the impact of distinct reaction and diffusion timescales, a photo‐active gripper is studied for robotic applications. Finally, a photo‐active microswimmer that exhibits non‐reciprocal motion is proposed to highlight the solvent diffusion for locomotion at the micro‐ and nano‐ scales. The work establishes that transient dynamics of chemo‐mechanical hydrogels generate functions not accessible by steady state models and provides a predictive platform for designing adaptive materials in emerging applications.

  PublisherOA PDFDOI

• Charge regulation effects on colloidal mixture nanoparticles

  The Journal of Chemical Physics · 2025-07-15 · 3 citations

  articleSenior author

  Changes in pH within a system containing dissociable sites affect the protonation and deprotonation of these groups, thereby influencing their physical properties. In response, the system modifies their surface charge, affecting electrostatic interactions, aggregation, stability, and structural behavior. Although the pH can be tuned in experiments, it is difficult to model this phenomenon using simulations or theoretical approaches. Here, we perform hybrid Monte Carlo-molecular dynamics simulations to model charge regulation effects in an equimolar colloidal charged system. We compare charge regulation effects with those of a system in which the charges of colloidal nanoparticles are not dissociable. The comparison between the two cases modifies the phase diagram, and it changes the volume fraction where a percolation network of nanoparticles is found. Charge regulation is found to destroy network formation, as the charge in the nanoparticles is modified because of the cooperativity dependency of the degree of charge dissociation sites among the nanoparticles favoring cluster formation. Our work suggests that the ionic and/or electronic conductivity in functionalized nanoparticles can be modified by changing pH values. It also guides the experimental design of oppositely charged nanoparticles as inks for 3D printing processes.

  PublisherDOI

• The Role of Asparagine as a Gatekeeper Residue in the Selective Binding of Rare Earth Elements by Lanthanide‐Binding Peptides

  Chemistry - A European Journal · 2025-05-01 · 3 citations

  articleOpen access

  Abstract Lanthanide‐binding tag (LBT) peptides selectively complex lanthanide cations (Ln 3+ ) in their binding pockets and are promising for lanthanide separation. However, designing LBTs that selectively target specific Ln 3+ cations remains a challenge due to limited molecular‐level understanding and control of interactions within the lanthanide‐binding pocket. In this study, we reveal that the N5 asparagine residue acts as a gatekeeper in the binding pocket, resulting in a 100‐fold selectivity for smaller Lu 3+ over larger La 3+ cations. Nuclear magnetic resonance spectroscopy and molecular dynamics simulations show that the N5 residue weakly binds to the larger La 3+ cation, permitting H 2 O molecules inside the pocket. For the smaller Lu 3+ cations, the N5 residue forms an inter‐arm hydrogen bond with the E14 glutamic acid residue, locking the Lu 3+ cation in the pocket and preventing H 2 O infiltration. Mutating the N5 asparagine to a D5 aspartic acid prevents such a hydrogen bond, eliminating the gatekeeping mechanism and precipitously reducing selectivity. The resulting binding affinity to Ln 3+ cations is non‐monotonic but generally increases with cation size. These results suggest a molecular design paradigm: the reduced affinity for larger lanthanides is due to open pocket conformations, while the selectivity of smaller Ln 3+ cations over larger ones is due to the gatekeeping hydrogen bond.

  PublisherOA PDFDOI

• Active Ionic Fluxes Induce Symmetry Breaking in Charge-Patterned Nanochannels

  ArXiv.org · 2025-10-16

  preprintOpen accessSenior author

  Biological systems rely on autonomous modes of charge transport to transmit signals, whereas conventional artificial systems typically depend on external fields, such as voltage or pressure gradients, limiting their adaptability. Here we investigate nanochannels in which an electrolyte is confined by symmetric boundary configurations combining patterned surface charge with active ionic fluxes. We show that the interplay between diffusive, electrostatic and hydrodynamic interactions in such active-charged nanosystems can trigger a symmetry breaking as the activity increases. Our results suggest that active-charged nanochannels could amplify directed flows up to the order of meters per second, opening pathways toward adaptable iontronic devices and neuromorphic architectures.

  PublisherOA PDFDOI

Recent grants

• MRSEC: Multifunctional Nanoscale Material Structures

  NSF · $13.2M · 2005–2012

• CDS&E: Organization and Dynamics of Charged Molecules in Heterogeneous Media

  NSF · $315k · 2016–2019

• Collaborative Research: NSF-EC Cooperative Activity in Computational Materials Research: Multiscale Modeling of Nanostructured Interfaces for Liquid Crystal Based Sensors

  NSF · $226k · 2005–2009

• Organization of charged molecules in heterogeneous media

  NSF · $300k · 2013–2016

• Segregation in Multicomponent Macromolecular Systems

  NSF · $300k · 2004–2008

Frequent coauthors

• Chad A. Mirkin

  Northwestern University

  69 shared

• Francisco J. Solis

  Arizona State University

  52 shared

• Baofu Qiao

  Northwestern University

  46 shared

• Samuel I. Stupp

  Northwestern University

  45 shared

• Jos W. Zwanikken

  Delft University of Technology

  42 shared

• Rastko Sknepnek

  35 shared

• Michael J. Bedzyk

  35 shared

• Martin Girard

  Max Planck Institute for Polymer Research

  32 shared

Awards & honors

• Member of the American Philosophical Society (2020)
• Polymer Prize of the American Physical Society (2017)
• Miller Institute Visiting Professor, University of Californi…
• Elected member of the National Academy of Sciences (2012)
• American Academy of Arts and Sciences Fellow (2010)