About

Arpit N Patel, MD, is an Assistant Professor of Clinical Anesthesiology and Critical Care at the University of Pennsylvania's Perelman School of Medicine. He serves as the Medical Director at the University of Pennsylvania and is part of the Department of Anesthesiology and Critical Care at the Hospital of the University of Pennsylvania. Dr. Patel completed his undergraduate studies in Biological Sciences at Rutgers University in 2008 and earned his MD from Robert Wood Johnson Medical School in 2012. His professional focus includes patient care, anesthesiology, critical care, and tele-critical care, with research contributions in sepsis management and related critical care topics.

Research topics

• Physics
• Biophysics
• Biochemistry
• Biology
• Chemical physics
• Chemistry
• Organic chemistry

Selected publications

• Engineering Antifreeze Proteins to Optimally Resist Engulfment by Ice

  The Journal of Physical Chemistry B · 2026-05-05

  articleSenior authorCorresponding

  Antifreeze proteins (AFPs) facilitate the survival of organisms in cold climates by inhibiting the growth and/or recrystallization of ice. To function, AFPs must first bind to ice crystals; bound AFPs must then resist engulfment by using their nonbinding side (NBS) to pin the ice–water interface. Here, we seek to understand how the molecular characteristics of an NBS, such as its ice-phobicity or shape, influence its ability to resist engulfment. By characterizing the free energy barriers that impede the engulfment of model AFPs, we find that the critical supercooling ΔT*, above which an AFP is engulfed, is dictated by an optimal pinning site on the NBS. We further find that the optimal pinning site is determined by an interplay between the contact line perimeter P and a pinning efficiency η, with ΔT* ∝ ηP at the optimal pinning site. For a hemispherical AFP, which displays progressively inward tapering, we find that η increases during engulfment, whereas P decreases; conversely, an NBS with outward tapering can achieve high P, but it suffers from low η. Because the product of η and P determines ΔT*, the inverse correlation between them limits ΔT*. To circumvent such limiting behavior, we propose an NBS shape with an outward bulge; by initially tapering outward, a bulged NBS permits higher P, and by subsequently tapering inward, it promotes high η as well. Importantly, we find that ΔT* is enhanced by more than a factor of 2 with an outward bulge of only 1 nm. We also find that the more ice-phobic an NBS is, the more efficiently it pins the ice–water interface, resulting in a higher ΔT*. Our findings shed light on how the NBS molecular characteristics influence ΔT* and suggest strategies for engineering the NBS to optimally resist engulfment by ice.

  PublisherDOI

• Anion transport and selectivity in ordered nanoporous polymers with 1 nm scale charged pores

  ChemRxiv · 2026-04-02

  articleOpen access

  Solvated ions of the same valency and charge exhibit minor differences in bulk transport but may display strong ion-specific effects in nanoscale environments. Investigating such effects is challenged by the heterogeneous nature of conventional nanostructured membranes, which can smear out underlying structure-property correlations. We use a combination of electrochemical impedance spectroscopy, two-dimensional infrared spectroscopy, NMR relaxometry, and molecular dynamics simulations to systematically investigate anion transport in nanoporous polymers with uniform charged 1 nm scale pores. The pores are water-containing channels formed by lyotropic self-assembly of positively charged amphiphilic monomers that are then crosslinked to produce a highly ordered nanoporous polymer. Across a series of monovalent anions, we observe strong correlations of activation energy and conductivity with hydration enthalpy – more strongly hydrated species have higher conductivity and lower activation energies. These effects originate from differences in pore-wall interactions and solvation shell behavior, with more weakly hydrated species showing larger departures from their bulk behavior in their water coordination and activation energy in the membrane. Our results indicate that pore confinement amplifies the impact of water contributions to ion motion. Specifically, the ability to maintain hydration shell waters and concomitantly, to avoid interactions with hydrophobic pore wall patches, leads to significant differences in transport, and to ion-specific trends that are unexpected in nanoporous materials. These results provide new insight into ion transport in highly confined and hydration-limited geometries and suggest a mechanism by which ion selectivity can be explicitly manipulated.

  PublisherOA PDFDOI

• Identifying Ice-Philic Protein Patches to Inform the Ice Binding Sites of Antifreeze Proteins

  ChemRxiv · 2026-04-24

  articleOpen accessSenior author

  Antifreeze proteins (AFPs) inhibit ice growth and recrystallization by binding to ice crystals via specific regions on their surface, known as ice-binding sites (IBS). Although the IBS of certain AFPs display regularly-spaced threonine residues that are matched well with the molecular spacings in ice crystals, the IBS of other AFPs lack such structural signatures, making it challenging to identify them. To address this challenge, we introduce a computational framework that systematically promotes ice formation in the AFP hydration shell. We find that ice-philic AFP regions, which form ice in their vicinity most readily, exhibit strong correspondence with the experimentallydetermined IBS. Importantly, such correspondence is observed across a diverse set of AFPs, including those with and without a regular array of threonines. We hope that our framework will expedite the identification of ice-binding sites of newly discovered or designed AFPs.

  PublisherOA PDFDOI

• Application-based Modeling of I/O Reliability

  2025-03-30 · 1 citations

  article

  This work presents a novel approach for modeling reliability degradation in a stacked-device input/output (I/O) circuit test structure. A large experimental study was done to generate an empirical model using conventional reliability parameters, circuit settings, and board elements to provide an application-level degradation profile. The approach can be readily applied to other circuits, applications, and parameters.

  PublisherDOI

• The Effects of Morphology and Hydration on Anion Transport in Self-Assembled Nanoporous Membranes

  ACS Nano · 2025-01-09 · 9 citations

  article

  Ordered nanoporous polymer membranes offer opportunities for systematically probing the mechanisms of ion transport under confinement and for realizing useful materials for electrochemical devices. Here, we examine the impact of morphology and ion hydration on the transport of hydroxide and bromide anions in nanostructured polymer membranes with 1 nm scale pores. We use aqueous lyotropic self-assembly of an amphiphilic monomer, with a polymerizable surfactant to create direct hexagonal (HI) and gyroid mesophases. UV-induced cross-linking leads to the formation of nanoporous polymers with water continuous channels. The membranes are mechanically robust and chemically durable, resisting degradation during extended exposure to 1 M NaOH solutions. We use a combination of electrochemical impedance spectroscopy, pulsed-field gradient NMR spectroscopy, and molecular simulations to elucidate anion and water transport. The as-prepared hexagonal systems display higher conductivity and lower activation energies for both anions relative to the gyroid system. When compared at equivalent hydration, however, gyroid and hexagonal membranes show similar activation energies, with nearly identical conductivities at ambient temperatures. Both ionic conductivity and water diffusivity increase with increasing hydration. The water uptake as a function of relative humidity for the hexagonal and gyroid mesophases ultimately dictates the water diffusion and magnitude of the ionic conductivity, with the hexagonal system showing overall higher capacity for hydration and thus faster ion transport. The durability of these materials under aggressive alkaline conditions and their relatively high hydroxide ion conductivity suggest that these nanostructured polymers could be of interest as membranes for alkaline fuel cells.

  PublisherDOI

• Amphiphilic nanopores that condense undersaturated water vapor and exude water droplets

  Science Advances · 2025-05-21 · 4 citations

  articleOpen accessCorresponding

  Condensation of water vapor in confined geometries, known as capillary condensation, is a fundamental phenomenon with far-reaching implications. While hydrophilic pores enable liquid formation from undersaturated vapor without energy input, the condensate typically remains confined, limiting practical utility. Here, we explore the use of amphiphilic nanoporous polymer-infiltrated nanoparticle films that condense and release liquid water under isothermal and undersaturated conditions. By tuning the polymer fraction and nanoparticle size, we optimize condensation and droplet formation. As vapor pressure increases, voids fill with condensate, which subsequently exudes onto the surface as microscopic droplets. This behavior, enabled by a balance of polymer hydrophobicity and capillarity, reveals how amphiphilic nanostructures can drive accessible water collection. Our findings provide design insights for materials supporting energy-efficient water harvesting and heat management without external input.

  PublisherDOI

• Thermodynamics of Self Assembly and Supramolecular Transitions using Enhanced Sampling

  ChemRxiv · 2025-01-08

  preprintOpen accessSenior author

  Computational studies of self-assembly have the potential to provide rich insights into their underlying thermodynamics and identify optimal system conditions for applications, such as nanomaterial synthesis or drug delivery. However, both self-assembly and supramolecular transitions can be hindered by free energy barriers, rendering them rare events on molecular timescales and making it challenging to sample them. Here, we show that the use of enhanced sampling techniques, when combined with a judiciously chosen set of order parameters, offers an efficient and robust route for characterizing the thermodynamics of self-assembly and supramolecular transitions. Specifically, we show that transitions between states with different periodicities or symmetries can be reversibly sampled by biasing a relatively small number of Fourier components of the particle density. We illustrate our approach by computing the free energy required to cleave a liquid slab and estimating the corresponding liquid-vapor surface tension. We also characterize the free energetics of the transition between spherical and rod-shaped droplets. These results serve as a first step towards the development of a systematic computational framework for exploring transitions in diverse supramolecular systems, such as surfactants or block copolymers, and characterizing the thermodynamics of their self-assembly.

  PublisherOA PDFDOI

• Thermodynamics of Self-Assembly and Supramolecular Transitions Using Enhanced Sampling

  Langmuir · 2025-06-02 · 3 citations

  articleSenior authorCorresponding

  Computational studies of self-assembly have the potential to provide rich insights into their underlying thermodynamics and identify optimal system conditions for applications such as nanomaterial synthesis or drug delivery. However, both self-assembly and supramolecular transitions can be hindered by free energy barriers, rendering them rare events on molecular time scales and making it challenging to sample them. Here, we show that the use of enhanced sampling techniques, when combined with a judiciously chosen set of order parameters, offers an efficient and robust route for characterizing the thermodynamics of self-assembly and supramolecular transitions. Specifically, we show that transitions between states with different periodicities or symmetries can be reversibly sampled by biasing a relatively small number of Fourier components of the particle density. We illustrate our approach by computing the free energy required to cleave a liquid slab and estimating the corresponding liquid-vapor surface tension. We also characterize the free energetics of the transition between spherical and rod-shaped droplets. These results serve as a first step toward the development of a systematic computational framework for exploring transitions in diverse supramolecular systems, such as surfactants or block copolymers, and characterizing the thermodynamics of their self-assembly.

  PublisherDOI

• Identifying and characterizing hydrophilic protein surface patches with molecular dynamics simulations

  Biophysical Journal · 2024-02-01

  articleSenior author
  PublisherDOI

• Interfacial Ice Density Fluctuations Inform Surface Ice-Philicity

  The Journal of Physical Chemistry B · 2024-08-22 · 3 citations

  articleSenior authorCorresponding

  The propensity of a surface to nucleate ice or bind to ice is governed by its ice-philicity─its relative preference for ice over liquid water. However, the relationship between the features of a surface and its ice-philicity is not well understood, and for surfaces with chemical or topographical heterogeneity, such as proteins, their ice-philicity is not even well-defined. In the analogous problem of surface hydrophobicity, it has been shown that hydrophobic surfaces display enhanced low water-density (vapor-like) fluctuations in their vicinity. To interrogate whether enhanced ice-like fluctuations are similarly observed near ice-philic surfaces, here we use molecular simulations and enhanced sampling techniques. Using a family of model surfaces for which the wetting coefficient, k, has previously been characterized, we show that the free energy of observing rare interfacial ice-density fluctuations decreases monotonically with increasing k. By utilizing this connection, we investigate a set of fcc systems and find that the (110) surface is more ice-philic than the (111) or (100) surfaces. By additionally analyzing the structure of interfacial ice, we find that all surfaces prefer to bind to the basal plane of ice, and the topographical complementarity of the (110) surface to the basal plane explains its higher ice-philicity. Using enhanced interfacial ice-like fluctuations as a measure of surface ice-philicity, we then characterize the ice-philicity of chemically heterogeneous and topologically complex systems. In particular, we study the spruce budworm antifreeze protein (sbwAFP), which binds to ice using a known ice-binding site (IBS) and resists engulfment using nonbinding sites of the protein (NBSs). We find that the IBS displays enhanced interfacial ice-density fluctuations and is therefore more ice-philic than the two NBSs studied. We also find the two NBSs are similarly ice-phobic. By establishing a connection between interfacial ice-like fluctuations and surface ice-philicity, our findings thus provide a way to characterize the ice-philicity of heterogeneous surfaces.

  PublisherDOI

Recent grants

• CAREER: Computational Characterization of Protein Hydration and Interactions

  NSF · $500k · 2017–2022

• EAGER: Collaborative Research: Type II: Data-Driven Characterization and Engineering of Protein Hydrophobicity

  NSF · $289k · 2019–2021

• Enhanced Sampling Methods for Characterizing Solvent Fluctuations in the Solvation Shells of Conformationally Flexible Molecules

  NSF · $360k · 2017–2021

• UNS: Molecular Modeling of Wetting and Dewetting Transitions on Nanotextured Surfaces

  NSF · $335k · 2015–2019

Frequent coauthors

• Nitash P. Balsara

  Lawrence Berkeley National Laboratory

  73 shared

• Suresh Narayanan

  Argonne National Laboratory

  46 shared

• Alec Sandy

  Argonne National Laboratory

  46 shared

• S. G. J. Mochrie

  Yale University

  46 shared

• Bruce A. Garetz

  New York University

  31 shared

• Hiroshi Watanabe

  Kyoto University

  31 shared

• Ferass M. Abuzaina

  25 shared

• Megan L. Ruegg

  Lawrence Berkeley National Laboratory

  25 shared

Labs

• Arpit N Patel LabPI