Mason, Thomas G.


Mason Thomas

Short Biography

Mason received dual B.S. degrees in physics (with high honors) and electrical engineering (summa cum laude) from the University of Maryland- College Park in 1989. Awarded an NSF graduate fellowship, he studied soft condensed matter physics at Princeton University and earned his Ph.D. in physics in 1995. His dissertation work revealed the roles of the glass transition and the jamming transition in the onset of low-frequency elasticity in concentrated, disordered colloidal dispersions of solid spheres and liquid droplets. Mason also created a new conceptual approach and developed an optical experimental method for measuring linear viscoelastic mechanical properties of soft materials; this approach is now known as thermal-entropic “passive” microrheology.

Mason’s first postdoctoral position was at the Centre de Recherche Paul Pascal (CNRS) in Bordeaux, France, where he explored the complex structure-flow-composition interplay in emulsification. His second postdoctoral position was in chemical and bio-engineering at Johns Hopkins University, where he developed the first particle tracking microrheology experiments and demonstrated these on biopolymer solutions, including ds-DNA. As a staff scientist and PI at ExxonMobil Research and Engineering Co., starting in 1997, he led research in light and small angle neutron scattering from asphaltenes in hydrocarbon systems involving heavy oils, resulting in two US patents and an internal commercialization that improved refinery productivity.

Joining UCLA in 2003 as an assistant professor of chemistry and of physics, he advanced to full professor in both departments in 2009. Prof. Mason leads an interdisciplinary research group that addresses important fundamental and applied questions in soft matter, biophysics, drug formulation and delivery, and translational medicine. Current topics being studied by Mason’s group  are: lithographic pre-assembly and self-assembly of systems of custom-shaped colloidal particles as molecular mimics, fabricating complex nanoemulsions via non-equilibrium routes for therapeutic and diagnostic purposes, modeling and improving passive microrheology, and passivated gel electrophoresis. Prof. Mason has over 130 publications in peer-reviewed journals, including Nature, Science, PNAS, PRL, and JACS, and 15 issued US patents, 13 of which are based on research at UCLA. He is a fellow and life member of the American Physical Society, a fellow of the American Association for the Advancement of Science, and a recipient of NSF’s Career Award.

Mason Lab Web Site »

Research Interests

Microrheology is the study of the deformation and flow of complex fluids at the microscale. As a graduate student, T.G. Mason invented an approach in 1993 for deducing local and macroscopic viscoelastic shear moduli of complex fluids by measuring the thermal fluctuations of colloidal particles introduced as probes. This approach, later published in Physical Review Letters in 1995 with his advisor D.A. Weitz (PRL 74 1250), sparked the modern field of microrheology. We continue research on glasses using thermal microrheology; our group also uses laser tweezers to manipulate dielectric probe microparticles such as polystyrene spheres and wax disks in order to investigate non-linear rheological properties.

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  • Microrheology: measuring the dynamic mechanical shear properties of viscoelastic soft materials over an extraordinarily large range of time scales by optically observing the diffusive motion of micron-sized probe particles embedded in these materials
  • Shear-induced structures in complex fluids: emulsification, shear-banding, shear-ordering
  • Neutron and light scattering from nanomaterials: asphaltenes, clays, droplets, polymers
  • Directed assembly of nanoparticles in solution using shape-dependent attractive interactions
  • Free boundary flows in microfluidic devices
  • Structure and dynamics of soft colloidal glasses

Honors & Awards

  • 2021: Fellow of Society of Rheology
  • 2019: Fellow of the American Association for the Advancement of Science
  • 2018: Rheologica Acta Publication Award
  • 2008: Fellow of the American Physical Society
  • 2008: Herbert Newby McCoy Award for Research Excellence (UCLA Dept. of Chemistry & Biochemistry)
  • 2007: Gallery of Fluid Motion Award (American Institute of Physics and APS DFD)
  • 2006: Intel New Faculty Award (Intel Corporation)
  • 2006: Glenn T. Seaborg Award (Beta Gamma Chapter of Alpha Chi Sigma)
  • 2006: Gallery of Fluid Motion Award (American Institute of Physics and APS DFD)
  • 2005: NSF CAREER Award (National Science Foundation)
  • 2003: John McTague Career Development Chair (UCLA Dept. of Chemistry & Biochem.)
  • 1992: Exxon Graduate Research Fellow
  • 1989: NSF Graduate Research Fellow (National Science Foundation)
  • 1989: Joseph Henry Prize in Physics (Princeton University)
  • 1989: Summa cum Laude in Physics and Electrical Engineering (University of Maryland, College Park)
  • 1985: Chancellor’s Scholar (University of Maryland, College Park)

Representative Publications

Complete List of Publications »

Selected Publication List  (2015 – Present)

  • Ultrastable nanoemulsions in disordered and ordered states. TG Mason, M Pagenkopp, US Patent App. 17/466,621 (2022)
  • Colliding and reacting molecules and colloids electrophoretically. TG Mason, DA Bikos, US Patent App. 17/373,431 (2022).
  • Curvature-assisted self-assembly of Brownian squares on cylindrical surfaces. H Liu, Y Zong, M Zu, TG Mason, F Ye, K Zhao, Journal of Colloid and Interface Science 605, 863-870 (2022).
  • Phase behavior of rotationally asymmetric Brownian kites containing 90° internal angles. H Liu, Y Zong, Z Hou, TG Mason, K Zhao, Chinese Physics B 30 (12), 124701 (2021).
  • Depletion torques between anisotropic colloidal particles. TG Mason, The Journal of Chemical Physics 155 (14), 144903 (2021).
  • Brownian lithographic polymers of steric lock-and-key colloidal linkages. T Yu, TG Mason, Science Advances 7 (36), eabg3678 (2021).
  • Multi-scale pre-assembled phases of matter. TG Mason, PY Wang, US Patent 11,052,700 (2021).
  • Self-motion and heterogeneous droplet dynamics in moderately attractive dense emulsions. HS Kim, Y Xu, F Scheffold, TG Mason, Journal of Physics: Condensed Matter 33 (17), 175101 (2021).
  • Diffusing Wave Microrheology of Strongly Attractive Dense Emulsions. Y Xu, F Scheffold, TG Mason, Physical Review E 102 (6), 062610 (2020).
  • Emergent Tetratic Order in Crowded Systems of Rotationally Asymmetric Hard Kite Particles. Z. Hou, Y. Zong, Z. Sun, F. Ye, T.G. Mason, and K. Zhao, Nat. Commun . 11 2064 (2020).
  • Long-Wavelength Fluctuations and Anomalous Dynamics in 2-Dimensional Liquids. Y.-W. Li, C.K. Mishra, Z.-Y. Sun, K. Zhao, T.G. Mason, R. Ganapathy, and M.P. Ciamarra, Proc. Natl. Acad. Sci. USA 116 22977-22982 (2019).
  • Band-Collision Gel Electrophoresis. D.A. Bikos and T.G. Mason, Nat. Commun. 10 3631 (2019).
  • Diffusing Wave Microrheology of Highly Scattering Monodisperse Concentrated Emulsions. H.S. Kim, N. Senbil, C. Zhang, F. Scheffold, and T.G. Mason, Proc. Natl. Acad. Sci. USA 116 7766-7771 (2019).
  • Crossover Between Athermal Jamming and the Thermal Glass Transition of Suspensions. M. Dinkgreve, M.A.J. Michels, T.G. Mason, and D. Bonn, Phys. Rev. Lett. 121 228001 (2018).
  • Vibrational Modes and Dynamic Heterogeneity in a Near-Equilibrium 2D Glass of Colloidal Kites. Y. Zong, K. Chen, T.G. Mason, and K. Zhao, Phys. Rev. Lett. 121 228003 (2018).
  • Assembly of Colloidal Particles in Solution. K. Zhao and T.G. Mason, Rep. Prog. Phys. 81 126601 (2018). > Invited review article.
  • A Brownian Quasi-Crystal of Pre-Assembled Colloidal Penrose Tiles. P.-Y. Wang and T.G. Mason, Nature 561 94-99 (2018). Featured in Physics World.
  • Influence of Ionic Constituents and Electrical Conductivity on the Propagation of Charged Nanoscale Objects in Passivated Gel Electrophoresis. D.A. Bikos and T.G. Mason, Electrophoresis 39 394-405 (2018).
  • Advances and Challenges in the Rheology of Concentrated Emulsions and Nanoemulsions. H.S. Kim and T.G. Mason, Adv. Colloid Interface Sci. 247 397-412 (2017). > Invited review article.
  • Dimer Crystallization of Chiral Proteoids. P.-Y. Wang and T.G. Mason, Phys. Chem. Chem. Phys. 19 7167-7175 (2017).
  • Treatment of Acidified Blood Using Reduced Osmolarity Mixed-Base Solutions. T.G. Mason and J.A. Kraut, Front. Physiol. 7 625 (2016).
  • Entropic, Electrostatic, and Interfacial Regimes in Concentrated Disordered Ionic Emulsions. H.S. Kim, F. Scheffold, and T.G. Mason, Rheol. Acta 55 683-697 (2016). > Received Rheol. Acta publication award in 2018.
  • Colloidal Lock-and-Key Dimerization Reactions of Hard Annular Sector Particles Controlled by Osmotic Pressure. P.-Y. Wang and T.G. Mason, J. Am. Chem. Soc. 137 15308-15314 (2015).
  • Shape-Designed Frustration by Local Polymorphism in a Near-Equilibrium Colloidal Glass. K. Zhao and T.G. Mason, Proc. Natl. Acad. Sci. USA 112 12063-12068 (2015).