Carnegie Mellon University
Department of Chemical Engineering
Department of Biomedical Engineering
Center for Complex Fluids Engineering
Center for Environmental Implications of Nanotechnology
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Professor Robert D. Tilton

Professor of Biomedical Engineering and Chemical Engineering
bob tilton
Bob Tilton has been a member of the Chemical Engineering faculty of Carnegie Mellon University since 1992. In 2004 he accepted a joint appointment in Biomedical Engineering. He completed the B.Ch.E. at the University of Delaware in 1986, and the M.S. and Ph.D. in Chemical Engineering at Stanford University in 1987 and 1991, respectively. His Ph.D. dissertation was recognized by the 1993 Victor K. LaMer Award for Outstanding Graduate Research in Colloid and Surface Chemistry from the American Chemical Society.  He conducted postdoctoral research in the Department of Chemistry at The Royal Institute of Technology and Institute for Surface Chemistry in Stockholm, Sweden.  He received the NSF Career Award in 1996.

He currently serves as Director of Carnegie Mellon’s Center for Complex Fluids Engineering.  His research focuses on the nanometer-scale forces and structures that govern the macroscopic performance properties of complex fluids and colloidal systems. This theme links fundamental work, for example on mechanisms of complexation and co-adsorption of polymers and surfactants, to more applied work, for example on the development of nanoparticles engineered for use as high-efficiency emulsifiers and surfactant systems for enhanced pulmonary drug delivery.

He has served as a regular member of the National Institutes of Health Nanotechnology Study Section and as Scientific Advisor to CODIRECT, the Institute Excellence Centre for Controlled Release and Delivery at the Institute for Surface Chemistry. He has held several leadership positions in the American Chemical Society Division of Colloid and Surface Chemistry, including service as the Victor K. LaMer Award Committee Chair, Symposium Committee Chair, Division Vice-Chair, Chair-Elect, Chair and Councilor. He co-chaired the 75th ACS Colloid and Surface Science Symposium at Carnegie Mellon in 2001 and was named a Fellow of the American Chemical Society in 2010. He was named a Fellow of the American Institute of Medical and Biological Engineers in 2013.

Current Members

Amy Stetten

Ph.D., expected 2017
Wean Hall 7336


Education History

2011 - PresentDoctor of Philosophy in Physics, Carnegie Mellon University
Masters of Science in Colloids, Polymers, and Surfaces, Carnegie Mellon University
2005 - 2009 Bachelor of Arts in Physics, Barnard College, Columbia University

Work History

2006-2010Engineering Assistant in the Alvin Group, Woods Hole OceanographicInstitute, Cape Cod

Research Interests

Lipid-induced Marangoni Spreading and Miscible Interface Behavior
Many treatments for chronic lung diseases rely on the ability of therapeutic agents to be delivered directly to the lining of obstructed lungs. One way to improve drug distribution within the lung is to add surfactants to the drug formulations. These surfactants induce a surface tension gradient, which causes Marangoni flow, allowing therapeutic agents to spread deep into the lung and to coat the entire airway surface. My work focuses on the use of the lung's own natural phospholipids in surfactant-aided pulmonary drug delivery methods. Additionally, I study the interface behavior of aqueous drops being delivered onto an aqueous solution subphase. These drops maintain an "effective interface" for long times that may be studied using Young-Laplace theory.

Alex Bertuccio

Ph.D., expected 2017
Doherty Hall 2208

alex bertuccio
Education History

2013 - PresentDoctor of Philosophy in Chemical Engineering, Carnegie Mellon University
2011 - 2012Master of Science in Chemical Engineering, Manhattan College
2008 - 2011Bachelor of Science in Chemical Engineering, Manhattan College

Work History

Aug 2012 - May 2013Adjunct Instructor, Manhattan College, Bronx, NY.
Aug 2011 - May 2012Teaching Assistant, Manhattan College, Bronx, NY.

Research Interests

Nanoparticle Adhesion to Biopolymer Matrices

Silver nanoparticles are known to be an effective antimicrobial agent and have been used as a means of water remediation. However, it is unclear where these nanoparticles accumulate as well as the impact that they have on the biological structures in the environment. It has been previously observed that microbes have a preference for growing on surfaces coated by silver nanoparticles when compared to a non-coated surface. We are currently investigating if microbial growth is selective to the type of coated surface or if any coating promotes growth.

Brittany Nordmark (co-advised, T. Pryzbycien)

Ph.D., expected 2018
Doherty Hall 2208

brittany nordmark
Education History

2013 - PresentDoctor of Philosophy in Chemical Engineering, Carnegie Mellon University
2009 - 2013Bachelor of Science in Chemical Engineering, University of Maryland, Baltimore County

Work History

May 2012 - Aug 2012Environmental Health and Safety Intern. GE Aviation/Middle River Aircraft Systems, Middle River, MD.
May 2008 - Aug 2010Laboratory Assistant Intern, United States Army Medical Research Institute of Chemical Defense, Aberdeen Proving Grounds, Edgewood, MD.

Research Interests

Immobilization of Moringa oleifera protein for sustainable water disinfection systems.
We are interested in studying the adsorption mechanism of Moringa oleifera cationic protein (MOCP) to silica and sand surfaces for water treatment purposes. MOCP acts as an antimicrobial in water treatment; however, Moringa oleifera seeds release organic matter that promotes the growth of microbes. Once the adsorption mechanism of MOCP is understood, we will move to studying methods of immobilizing the protein that will minimize excess organic matter release. Ellipsometry is used to determine adsorption kinetics and extension of adsorption of MOCP.

Yun-Ru Huang

Ph.D., expected 2018
Doherty Hall 2208


Education History

2014 - Present
Doctor of Philosophy in Chemical Engineering, Carnegie Mellon University
2011 - 2013
Master of Science in Chemical and Biomolecular Engineering, University of Pennsylvania
2007 - 2011Bachelor of Science in Chemical Engineering, National Taiwan University

Work History
Sep 2012 - Jun 2014Research Assistant, Dept. of Chemical and Biomolecular Engineering, University of Pennsylvania.
Jun 2012 - Aug 2012
Intern, Taiwan Semiconductor Manufacturing Company, Taiwan.

Research Interests

Polymer Brush-Grafted Nanoparticle Emulsifiers
Nanoparticles grafted with polymers have proven to be highly efficient emulsifiers and can be used to stabilize a large interfacial area with very low particle concentrations at the oil/water interface compared to conventional particulate emulsifiers.  However, the reason why particles with different physico-chemical properties produce emulsions with similar stability yet display different efficiencies is unclear.  We are studying the surface pressure and dilatational elastic modulus using silicon nanoparticles grafted with PDMAEMA brushes and investigating the fundamental interfacial phenomena responsible for this emulsifying efficiency.

Steven Iasella (co-advised, T. Pryzbycien, S. Garoff)

Ph.D., expected 2019
Wean Hall 7332

Education History

2014 - PresentDoctor of Philosophy in Chemical Engineering, Carnegie Mellon University
2007 - 2011Bachelor of Chemical and Petroleum Engineering, University of Pittsburgh
Work History


Research Assistant, Department of Chemical and Petroleum Engineering, University Pittsburgh

Research Interests

Marangoni Spreading on Hydrogel Supported Thin Films
Past research in our group has focused on using Marangoni driven spreading to move various chemicals across the surfaces of entangled polymeric solutions. This phenomenon can potentially be used to move drugs past mucous blockages common to various types of lung disease. Most of the work, both from within our group and outside it, has been using cm thick liquid pools. This is a very different environment than the hundreds of microns thick fluid layers found in the lung.  To further complicate things, the airways surface layer can be divided up into two distinct regions: the mucin raft and the pericilliary layer.  These two layers have very different properties.  It is my goal to investigate how spreading behaves on these thin two layer systems in order to better understand what aerosol formulations would be most effective for treating obstructive pulmonary diseases.

Danish Iqbal

Ph.D., expected 2020
Doherty Hall 2208

Danish Iqbal

Education History

2011 – 2015

Bachelor of Science in Chemical Engineering, University of Southern California

2015 – Present Doctor of Philosophy in Chemical Engineering, Carnegie Mellon University

Work History

September 2009 – December 2009

Teaching Assistant, Mork Family Department of Chemical Engineering and Material Science, University of Southern California

May 2010 – May 2011 Research Assistant, Mork Family Department of Chemical Engineering and Material Science, University of Southern California

Research Interests

Polymer Grafted Magnetic Nanoparticles for soft micro-actuators

We are interested in forming soft micro-actuators by grafting thermo- and photo- responsive polymers to the surface of magnetic nanoparticles. The magnetic nanoparticles can be aligned in an electric field and the polymers will be designed so that they will swell and shrink in response to light. By doing so, we hope to create a micro-actuators that are capable of reversibly expanding and contracting to be used for useful work.

Bhagyashree Lele

Ph.D., expected 2020
Doherty Hall 2100 D

Education History

2016 – Present

Doctor of Philosophy in Chemical Engineering, Carnegie Mellon University

2014 – 2015

Master of Science in Chemical Engineering and Colloids, polymers and surfaces, Carnegie Mellon University

2010 – 2014

Bachelor of Chemical Engineering, Institute of Chemical Technology, Mumbai, India

Work History

March 2016 - May 2016

Staff Research Associate, University of California, Santa Barbara

May 2013 - June 2013

Operations intern, Hindustan Petroleum Corporation Limited, Mumbai Refinery.

May 2012 - June 2012

Research intern, Institute of Chemical Technology, Mumbai, India.

Research Interests

Control of colloidal forces by synergistic polymer/surfactant complexation.

The forces acting between suspended particles control stability of a colloidal suspension. Understanding the nature and range of these forces is important to formulate a stable suspension. We are interested in investigating the range and magnitude of depletion forces between suspended colloidal particles in the presence of polymer/surfactant complexes. Depletion forces have been measured for various depletants individually, yet the synergistic effect in multicomponent systems is unclear. We will also be studying the dependence of depletion forces on the structure and charge of various polymer/surfactant complexes under varying ionic strength and pH. Colloidal Probe Atom Force Microscopy will be used to measure the forces between a silica sphere and silica wafer under aqueous conditions.

Group Alumni

NameGraduation YearThesis
Ramankur Sharma
(co-advised, T. Pryzbycien and S. Garoff)
2016Marangoni Driven Spreading on Entangled Aqueous Polymer Solutions with Applications to Pulmonary Drug Delivery
John K. Riley2016Nanotribology and Surface Forces between Adsorbed Layers of Spherical Polymer Brushes
Amsul Khanal
(co-advised, T. Pryzbycien and S. Garoff)
2014Spreading of Surfactant-laden Aerosols on Entangled Polymer Solution Subphases
Stacey Louie (CEE)
(co-advised, G. Lowry)
2014Characterization and Modeling of Macromolecules on Nanoparticles and their Effects on Nanoparticle Aggregation
Adam L. Canady2013Adsorption of Poly(Ethylene Glycol) Conjugated Proteins to Oil/Water Interfaces Relevant to Drug Delivery
Stacy M. Wirth2013Impacts of Silver Nanoparticles on Bacterial Biofilms
Teresa L. Kirschling
(minor advisor, G. Lowry)
2011Interactions of Microbial Communities with Engineered Nanoparticles in Environmental Systems
Sheetal Pai
(co-advised, T. Pryzbycien)
2011Adsorption of Poly(Ethylene Glycol) Conjugated Proteins to Biomaterials used in Delivery
Trishna Saigal2011Development of Novel Pickering Emulsifiers using Polymer Grafted Nanoparticles
Jit Kang Lim
(co-advised, S. Majetich)
2009Hybrid Magnetic Plasmonic Nanoparticles
Hye-Jin Kim (CEE)
(major advisor, G. Lowry)
2009Transport, Reactivity and Fate of Polyelectrolyte Modified Zero Valent Iron Nanoparticles used for Groundwater Remediation in Heterogeneous Porous Media
Tanapon Phenrat (CEE)
(major advisor, G. Lowry)
2008Effect of Polymeric Surface Modification on Nano-Sized Zero Valent Iron (NZVI) Aggregation, Transport of Concentrated NZVI Dispersions in Porous Media, and Reactivity with Trichloroethylene
Andy Kusumo
(co-advised, J. Schneider)
2008High Capacity Polyelectrolyte Brushes for Tuning Protein Adsorption
Kevin Sirk2007Polyelectrolyte Surface Modification of Reactive Iron Nanoparticles
Navid Bin Saleh (CEE)
(major advisor, G. Lowry)
2007An Assessment of Novel Polymeric Coatings to Enhance Transport and in Situ Targeting of Nanoiron for Remediation of Non-Aqueous Phase Liquids (NAPLs)
Jessica Tucker
(co-advised, T. Pryzbycien)
2006Novel Extracellular Matrix Mimics: Applications in Drug Delivery and protein-Receptor Binding
Marvi Matos
(co-advised, L. White)
2006Electroosmotic Mass Transport Control in Polyacrylamide Gels via Embedded Silica Nanoparticles
Jason Hamm
(co-advised, S. Garoff)
2005Redispersion of Polymer Coated Colloidal Aggregates with Changing Solvent Quality
Hao Zhao
(co-advised, L. White)
2005Electrohydrodynamic Patterning and Separation of Colloids or Cells
Susan Daly DiPasquo
(co-advised, T. Pryzbycien)
2004The Effect of Polyethylene Glycol Modification of Proteins on Adsorption Mechanisms
Derek Berglund
(co-advised, T. Pryzbycien)
2003Tuning Adsorption via Polymer-Surfactant Complexation
Alan Braem
(co-advised, D. Prieve)
2001Colloidal and Interfacial Phenomena in Polymer/Surfactant Mixtures
Stephanie Butler Velegol2000Tuning Interfacial and Bulk Self-Assembly of Ionic Surfactants via Counterions and Non-Binding Polyelectrolytes
Eric Tsung2000A Novel Total Internal Reflection Fluorescence Assay for the Catalytic Activity of Adsorbed Enzyme Monolayers
Joon-Hyung Kim1999Pyrene Solubilization in Micelles and Polymer-Surfactant Complexes
Michelle Lourette Sun1999Coadsorption of Strongly Interacting Proteins and Surfactants
Edward S. Pagac1997Colloidal Forces in the Presence of  Polymers and Surfactants
James R. Charron1996Block Copolymer Adsorption to Phospholipid Monolayers at the Air-Water Interface
Julie L. Robeson1995Application of Total Internal Reflection Fluorescence to Probe Surface Diffusion and Orientation of Adsorbed Proteins

NameGraduation YearThesis
Wenjie Wu2017Phase Stability and Size Characterization of Stimuli-Responsive Star Polymers
Sachi Nagada2017Spray Drying of Model Pharmaceutical Powders Containing Surfactants as Dispersal Aids
Haichao Wu2016Marangoni Driven Dewetting of Thin Liquid Layers in a Cylinder
Emily Wallitsch2015A Comparison on Equilibrium Interfacial Properties of PEO Linear Polymers and Spherical Brushes at the Air/Water Interface
Ran Li2014Colloidal Particle Adhesion in Solutions of Polymer/Surfactant Mixtures
Owaiz Ebrahim2014Competitve Adsorption of Polymers with Complex Architectures
Feng Cao2013Nanoparticle colloidal stability in biofilms
Shih-hsin Chiang2013Interfacial tension between PEGylated protein solutions and organic polymer solutions
Chiang-Yu Wang2013Associative thickener effects on brush grafted nanoparticle stabilized emulsions
Zhenhuan Zhong2013Electrokinetics of solids coated with brush grafted nanoparticles
Yao Yu
(co-advised, T. Pryzbycien)
2013Sustained release of PEGylated RNase A from PLG microspheres prepared with butyl acetate as organic solvent
Sneha Solanki
(co-advised, T. Pryzbycien and S. Garoff)
2012Comparison of surfactant effectiveness in enhancing deposited aerosol spreading with application to pulmonary delivery
Ramankur Sharma
(co-advised, T. Pryzbycien and S. Garoff)
2011Spreading and wetting characteristics of a drop of pure surfactant and surfactant solution on liquid subphases
Roomi Kalita
(co-advised, T. Pryzbycien and S. Garoff)
2011Incomplete spreading of surfactants and surfactant solutions on liquid subphases: a proof of surfactant moving ahead of contact lines and the origin of autophobing
Caitlyn Trombly2010Macromolecule Adsorption to Silver Nanoparticles
Don Jin Seo
(co-advised, S. Majetich)
2009Preparation of Optically Detectable Magnetic Iron Oxide Nanorods
Chiung-Hsuan Chung
(co-advised, S. Garoff)
2008Marangoni Driven Flow of Surfactant Solutions on Polymer Solution Subphase”
Marianne Mota
(co-advised, T. Pryzbycien)
2008In Vitro Release of Poly(Ethylene Glycol) Modified Proteins from Biodegradable Depots
Sichol Srithavatchai2005Origins of Persistent Non-Equilibrium States in Co-Adsorbed Layers of Polymers and Surfactants
JitKang Lim
(co-advised, S. Majetich)
2005Electrohydrodynamic Technique for Spatial and Temporal Control of Reactions in Microfluidic Systems
Prasad NSB1994Estimation of Intermolecular Forces between Adsorbed Proteins via Optical Reflectometry and Monte Carlo Simulations
Thomas E. Rabe1992The Role of Surface Flexibility in the Surface Diffusion of Adsorbed Proteins


NameTenureProject Title
Gunnar Duner, Ph.D.
(joint supervised, S. Garoff and T. Pryzbycien)
2014-2016Adsorption and Interfacial Transport of ZPT Microparticles
Nintin Kumar, Ph.D.
(joint supervised, S. Garoff)
2001-2003Nonionic surfactant adsorption and dynamic wetting

Visiting Graduate Students
Junxue An
(Ph.D., KTH Royal Instiute of Technology, Stockholm, Sweden)
Jan - June 2014Anionic surfactant uptake by high-grafting density cationic polyelectrolyte brush-grafted nanoparticles
Maria Lundin.
(Ph.D., KTH Royal Institue of Technology, Stockholm, Sweden)
Sept - Dec 2007Inter- and intra-layer diffusion in layer by layer assembled polyelectrolyte multilayers