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Shrivastava S, Ifra, Saha S, Singh A. Dissipative particle dynamics simulation study on ATRP-brush modification of variably shaped surfaces and biopolymer adsorption. Phys Chem Chem Phys 2022; 24:17986-18003. [PMID: 35856807 DOI: 10.1039/d2cp01749k] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a dissipative particle dynamics (DPD) simulation study on the surface modification of initiator embedded microparticles (MPs) of different shapes via atom transfer radical polymerization (ATRP) brush growth. The surface-initiated ATRP-brush growth leads to the formation of a more globular MP shape. We perform the comparative analysis of ATRP-brush growth on three different forms of particle surfaces: cup surface, spherical surface, and flat surface (rectangular/disk-shaped). First, we establish the chemical kinetics of the brush growth: the monomer conversion and the reaction rates. Next, we discuss the structural changes (shape-modification) of brush-modified surfaces by computing the radial distribution function, spatial density distribution, radius of gyration, hydrodynamic radius, and shape factor. The polymer brush-modified particles are well known as the carrier materials for enzyme immobilization. Finally, we study the biopolymer adsorption on ATRP-brush modified particles in a compatible solution. In particular, we explore the effect of ATRP-brush length, biopolymer chain length, and concentration on the adsorption process. Our results illustrate the enhanced biopolymer adsorption with increased brush length, initiator concentration, and biopolymer concentration. Most importantly, when adsorption reaches saturation, the flat surface loads more biopolymers than the other two surfaces. The experimental results verified the same, considering the disk-shaped flat surface particles, cup-shaped particles, and spherical particles.
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Affiliation(s)
- Samiksha Shrivastava
- Department of Physics, Indian Institute of Technology (BHU), Varanasi-221005, Uttar Pradesh, India.
| | - Ifra
- Department of Materials Science and Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - Sampa Saha
- Department of Materials Science and Engineering, Indian Institute of Technology Delhi, New Delhi-110016, India
| | - Awaneesh Singh
- Department of Physics, Indian Institute of Technology (BHU), Varanasi-221005, Uttar Pradesh, India.
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2
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Liu Y, Aizenberg J, Balazs AC. Using Dissipative Particle Dynamics to Model Effects of Chemical Reactions Occurring within Hydrogels. NANOMATERIALS 2021; 11:nano11102764. [PMID: 34685205 PMCID: PMC8540124 DOI: 10.3390/nano11102764] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 10/11/2021] [Accepted: 10/14/2021] [Indexed: 11/25/2022]
Abstract
Computational models that reveal the structural response of polymer gels to changing, dissolved reactive chemical species would provide useful information about dynamically evolving environments. However, it remains challenging to devise one computational approach that can capture all the interconnected chemical events and responsive structural changes involved in this multi-stage, multi-component process. Here, we augment the dissipative particle dynamics (DPD) method to simulate the reaction of a gel with diffusing, dissolved chemicals to form kinetically stable complexes, which in turn cause concentration-dependent deformation of the gel. Using this model, we also examine how the addition of new chemical stimuli and subsequent reactions cause the gel to exhibit additional concentration-dependent structural changes. Through these DPD simulations, we show that the gel forms multiple latent states (not just the “on/off”) that indicate changes in the chemical composition of the fluidic environment. Hence, the gel can actuate a range of motion within the system, not just movements corresponding to the equilibrated swollen or collapsed states. Moreover, the system can be used as a sensor, since the structure of the layer effectively indicates the presence of chemical stimuli.
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Affiliation(s)
- Ya Liu
- Chemical and Petroleum Engineering Department, University of Pittsburgh, Pittsburgh, PA 15261, USA;
| | - Joanna Aizenberg
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA 02138, USA;
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA 02138, USA
| | - Anna C. Balazs
- Chemical and Petroleum Engineering Department, University of Pittsburgh, Pittsburgh, PA 15261, USA;
- Correspondence:
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Ifra, Singh A, Saha S. Shape Shifting of Cup Shaped Particles on Growing poly (2‐hydroxy ethyl methacrylate) Brushes by “Grafting From” Approach and Dissipative Particle Dynamics Simulation. ChemistrySelect 2020. [DOI: 10.1002/slct.202000747] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Ifra
- Department of Materials Science and EngineeringIndian Institute of Technology Delhi New Delhi India
| | - Awaneesh Singh
- Department of PhysicsIndian Institute of Technology (BHU) Varanasi India
| | - Sampa Saha
- Department of Materials Science and EngineeringIndian Institute of Technology Delhi New Delhi India
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4
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Ren L, Cheng Y, Wang Q, Tian X, Yang J, Zhang D. Relationship between corrosion product and fouling growth on mild steel, copper and brass surface. Colloids Surf A Physicochem Eng Asp 2020. [DOI: 10.1016/j.colsurfa.2020.124502] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Zhang CT, Liu Y, Wang X, Wang X, Kolle S, Balazs AC, Aizenberg J. Patterning non-equilibrium morphologies in stimuli-responsive gels through topographical confinement. SOFT MATTER 2020; 16:1463-1472. [PMID: 31859307 DOI: 10.1039/c9sm02221j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Stimuli-responsive "smart" polymers have generated significant interest for introducing dynamic control into the properties of antifouling coatings, smart membranes, switchable adhesives and cell manipulation substrates. Switchable surface morphologies formed by confining stimuli-responsive gels to topographically structured substrates have shown potential for a variety of interfacial applications. Beyond patterning the equilibrium swelling behavior of gels, subjecting stimuli-responsive gels to topographical confinement could also introduce spatial gradients in the various timescales associated with gel deformation, giving rise to novel non-equilibrium morphologies. Here we show how by curing poly(N-isopropylacrylamide) (pNIPAAm)-based gel under confinement to a rigid, bumpy substrate, we can not only induce the surface curvature to invert with temperature, but also program the transient, non-equilibrium morphologies that emerge during the inversion process through changing the heating path. Finite element simulations show that the emergence of these transient morphologies is correlated with confinement-induced gradients in polymer concentration and position-dependent hydrostatic pressure within the gel. To illustrate the relevance of such morphologies in interfacial applications, we show how they enable us to control the gravity-induced assembly of colloidal particles and microalgae. Finally, we show how more complex arrangements in particle assembly can be created through controlling the thickness of the temperature-responsive gel over the bumps. Patterning stimuli-responsive gels on topographically-structured surfaces not only enables switching between two invertible topographies, but could also create opportunities for stimuli ramp-dependent control over the local curvature of the surface and emergence of unique transient morphologies. Harnessing these features could have potential in the design of multifunctional, actuatable materials for switchable adhesion, antifouling, cell manipulation, and liquid and particle transport surfaces.
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Affiliation(s)
- Cathy T Zhang
- Harvard John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, MA, USA.
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6
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Chen S, Yong X. Dissipative particle dynamics modeling of hydrogel swelling by osmotic ensemble method. J Chem Phys 2018; 149:094904. [DOI: 10.1063/1.5045100] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Affiliation(s)
- Shensheng Chen
- Department of Mechanical Engineering, Binghamton University, The State University of New York, 4400 Vestal Parkway East, Binghamton, New York 13902, USA
| | - Xin Yong
- Department of Mechanical Engineering, Binghamton University, The State University of New York, 4400 Vestal Parkway East, Binghamton, New York 13902, USA
- Institute for Materials Research, Binghamton University, The State University of New York, 4400 Vestal Parkway East, Binghamton, New York 13902, USA
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Shen L, Ding HM, Ma YQ. Computational Design of a Functionalized Substrate for Capturing Nanoparticles with Specific Size and Shape. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:9829-9835. [PMID: 30056705 DOI: 10.1021/acs.langmuir.8b01398] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
The efficient capture of nanoscopic particulates plays a key role in many scientific fields like filtration and fabrication of nanocomposites as well as biosensors. In this work, we design two types of nanosubstrates to capture the nanoparticle with specific property by using Brownian dynamics simulations. It is found that the substrate coated with copolymers (composed of nonspecific block and specific block) can be used to capture the nanoparticle with different sizes but its capture efficiency of nanoparticles with different shapes is very low. To overcome such problem, the other substrate containing shaped holes is also designed. By conducting a serial of control simulations, we find that the nonspecific polymers at the bottom and on the rim of the hole have great impact on the sensitive capture. The present study may provide some physical insights into the experimental design of nanodevices in real applications.
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Affiliation(s)
- Lin Shen
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology , Soochow University , Suzhou 215006 , China
| | - Hong-Ming Ding
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology , Soochow University , Suzhou 215006 , China
| | - Yu-Qiang Ma
- Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology , Soochow University , Suzhou 215006 , China
- National Laboratory of Solid State Microstructures and Department of Physics, Collaborative Innovation Center of Advanced Microstructures , Nanjing University , Nanjing 210093 , China
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Waters JT, Liu Y, Li L, Balazs AC. Optimizing Micromixer Surfaces To Deter Biofouling. ACS APPLIED MATERIALS & INTERFACES 2018; 10:8374-8383. [PMID: 29425023 DOI: 10.1021/acsami.7b19845] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Using computational modeling, we show that the dynamic interplay between a flowing fluid and the appropriately designed surface relief pattern can inhibit the fouling of the substrate. We specifically focus on surfaces that are decorated with three-dimensional (3D) chevron or sawtooth "micromixer" patterns and model the fouling agents (e.g., cells) as spherical microcapsules. The interaction between the imposed shear flow and the chevrons on the surface generates 3D vortices in the system. We pinpoint a range of shear rates where the forces from these vortices can rupture the bonds between the two mobile microcapsules near the surface. Notably, the patterned surface offers fewer points of attachment than a flat substrate, and the shear flows readily transport the separated capsules away from the layer. We contrast the performance of surfaces that encompass rectangular posts, chevrons, and asymmetric sawtooth patterns and thereby identify the geometric factors that cause the sawtooth structure to be most effective at disrupting the bonding between the capsules. By breaking up nascent clusters of contaminant cells, these 3D relief patterns can play a vital role in disrupting the biofouling of surfaces immersed in flowing fluids.
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Affiliation(s)
- James T Waters
- Chemical Engineering Department , University of Pittsburgh , Pittsburgh , Pennsylvania 15261 , United States
| | - Ya Liu
- Chemical Engineering Department , University of Pittsburgh , Pittsburgh , Pennsylvania 15261 , United States
| | - Like Li
- Department of Mechanical Engineering , Mississippi State University , Mississippi State , Mississippi 39762 , United States
| | - Anna C Balazs
- Chemical Engineering Department , University of Pittsburgh , Pittsburgh , Pennsylvania 15261 , United States
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Liu Y, Balazs AC. Modeling Biofilm Formation on Dynamically Reconfigurable Composite Surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2018; 34:1807-1816. [PMID: 29293347 DOI: 10.1021/acs.langmuir.7b03765] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
We augment the dissipative particle dynamics (DPD) simulation method to model the salient features of biofilm formation. We simulate a cell as a particle containing hundreds of DPD beads and specify p, the probability of breaking the bond between the particle and surface or between the particles. At the early stages of film growth, we set p = 1, allowing all bonding interactions to be reversible. Once the bound clusters reach a critical size, we investigate scenarios where p = 0, so that incoming species form irreversible bonds, as well as cases where p lies in the range of 0.1-0.5. Using this approach, we examine the nascent biofilm development on a coating composed of a thermoresponsive gel and the embedded rigid posts. We impose a shear flow and characterize the growth rate and the morphology of the clusters on the surface at temperatures above and below Tc, the volume phase transition temperature of a gel that displays lower critical solubility temperature (LCST). At temperatures above Tc, the posts effectively inhibit the development of the nascent biofilm. For temperatures below Tc, the swelling of the gel plays the dominant role and prevents the formation of large clusters of cells. Both these antifouling mechanisms rely on physical phenomena and, hence, are advantageous over chemical methods, which can lead to unwanted, deleterious effects on the environment.
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Affiliation(s)
- Ya Liu
- Chemical Engineering Department, University of Pittsburgh , 3700 O'Hara Street, Pittsburgh, Pennsylvania 15261, United States
| | - Anna C Balazs
- Chemical Engineering Department, University of Pittsburgh , 3700 O'Hara Street, Pittsburgh, Pennsylvania 15261, United States
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Zheng Y, Liu X, Xu J, Zhao H, Xiong X, Hou X, Cui J. Thermoresponsive Mobile Interfaces with Switchable Wettability, Optical Properties, and Penetrability. ACS APPLIED MATERIALS & INTERFACES 2017; 9:35483-35491. [PMID: 28945340 DOI: 10.1021/acsami.7b12354] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Liquid-based mobile interfaces, in which liquids are being utilized as structural long-term components, have shown their multifunctionality in materials science, such as the hydration layer of polyelectrolyte brushes used for artificial implants, stabilized lubricants for antibiofouling, anti-icing, self-cleaning, optical control, and so forth. However, these currently available systems do not usually show a response to environmental stimuli. Here, we describe a strategy for preparing thermoresponsive mobile interfaces made from novel silicone-based lubricants that display lower critical solution temperature and demonstrate their capabilities on controlling in situ water wetting and dewetting, thermo-gating penetration, and optical properties. These properties allow the mobile films to form a kind of erasable recording platforms. We foresee diverse applications in liquid transport, wetting and adhesion control, and transport switching.
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Affiliation(s)
- Yijun Zheng
- INM - Leibniz Institute for New Materials , Campus D2 2, Saarbrücken 66123, Germany
| | - Xiao Liu
- Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education, School of Biological Science and Medical Engineering, Beihang University , Beijing 100191, China
- Department of Medicine, Brigham and Women's Hospital, Harvard Medical School , Boston, Massachusetts 02139, United States
| | - Jiajia Xu
- INM - Leibniz Institute for New Materials , Campus D2 2, Saarbrücken 66123, Germany
| | - Huaixia Zhao
- INM - Leibniz Institute for New Materials , Campus D2 2, Saarbrücken 66123, Germany
- Institute for Fundamental and Frontier Science, University of Electronic Science and Technology of China , Chengdu 610054, China
| | - Xinhong Xiong
- INM - Leibniz Institute for New Materials , Campus D2 2, Saarbrücken 66123, Germany
| | - Xu Hou
- College of Chemistry and Chemical Engineering, Xiamen University , Xiamen 361005, China
- College of Physical Science and Technology, Xiamen University , Xiamen 361005, China
- Collaborative Innovation Center of Chemistry for Energy Materials , Xiamen 361005, China
| | - Jiaxi Cui
- INM - Leibniz Institute for New Materials , Campus D2 2, Saarbrücken 66123, Germany
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Qin S, Yong X. Interfacial adsorption of pH-responsive polymers and nanoparticles. SOFT MATTER 2017; 13:5137-5149. [PMID: 28657632 DOI: 10.1039/c7sm00637c] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Using dissipative particle dynamics (DPD), we model the interfacial adsorption of pH-responsive polyelectrolytes and polyelectrolyte-grafted nanoparticles (PNPs) at a planar water-oil interface. The electrostatic interactions in the presence of the dielectric discontinuity across the interface are modeled by exploiting the Groot method, which uses an iterative method to solve the Poisson equation on a uniform grid with distributed charge. We reveal the effects of the pH and salinity of the aqueous solution and the length of the polyelectrolyte on the adsorption behavior of weak polyelectrolytes. The adsorption kinetics is monitored via the trajectory of the center of mass of the polyelectrolyte in the direction normal to the interface. The residence time at the interface and the pair correlation function between the polyelectrolyte and the oil are measured to quantitatively characterize the adsorption. Similar to the weak polyelectrolytes, the influences of pH, salinity and grafted chain length on the adsorption of an individual PNP are explored. Our results show that by grafting polyelectrolytes, the interfacial behavior of the nanoparticles can be tuned by changing the pH and salinity of the solution, which is dictated by the contact angle, the pair correlation function between the particles and the oil, the desorption energy, and the particle morphology at the interface. We also observe that the electrostatic-driven variations in the interfacial activity and morphology of the PNPs are not sensitive to the length of the grafted polyelectrolytes.
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Affiliation(s)
- Shiyi Qin
- Department of Mechanical Engineering, Binghamton University, The State University of New York, Binghamton, New York 13902, USA.
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12
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Liu Y, Kuksenok O, He X, Aizenberg M, Aizenberg J, Balazs AC. Harnessing Cooperative Interactions between Thermoresponsive Aptamers and Gels To Trap and Release Nanoparticles. ACS APPLIED MATERIALS & INTERFACES 2016; 8:30475-30483. [PMID: 27547846 DOI: 10.1021/acsami.6b06575] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We use computational modeling to design a device that can controllably trap and release particles in solution in response to variations in temperature. The system exploits the thermoresponsive properties of end-grafted fibers and the underlying gel substrate. The fibers mimic the temperature-dependent behavior of biological aptamers, which form a hairpin structure at low temperatures (T) and unfold at higher T, consequently losing their binding affinity. The gel substrate exhibits a lower critical solution temperature and thus, expands at low temperatures and contracts at higher T. By developing a new dissipative particle dynamics simulation, we examine the behavior of this hybrid system in a flowing fluid that contains buoyant nanoparticles. At low T, the expansion of the gel causes the hairpin-shaped fibers to extend into the path of the fluid-driven particle. Exhibiting a high binding affinity for these particles at low temperature, the fibers effectively trap and extract the particles from the surrounding solution. When the temperature is increased, the unfolding of the fiber and collapse of the supporting gel layer cause the particles to be released and transported away from the layer by the applied shear flow. Since the temperature-induced conformational changes of the fiber and polymer gel are reversible, the system can be used repeatedly to "catch and release" particles in solution. Our findings provide guidelines for creating fluidic devices that are effective at purifying contaminated solutions or trapping cells for biological assays.
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Affiliation(s)
- Ya Liu
- Department of Chemical and Petroleum Engineering, University of Pittsburgh , Pittsburgh, Pennsylvania 15261, United States
| | - Olga Kuksenok
- Materials Science and Engineering Department, Clemson University , Clemson, South Carolina 29634, United States
| | - Ximin He
- Biodesign Institute, Arizona State University , Tempe, Arizona 85281, United States
- Materials Science and Engineering, School for Engineering of Matter, Transport and Energy, Arizona State University , Tempe, Arizona 85281, United States
| | - Michael Aizenberg
- Wyss Institute for Biologically Inspired Engineering, Harvard University , Cambridge, Massachusetts 02138, United States
| | - Joanna Aizenberg
- Wyss Institute for Biologically Inspired Engineering, Harvard University , Cambridge, Massachusetts 02138, United States
- Department of Chemistry and Chemical Biology, Harvard University , Cambridge, Massachusetts 02138, United States
- School of Engineering and Applied Science, Harvard University , Cambridge, Massachusetts 02138, United States
- Kavli Institute for Bionano Science and Technology, Harvard University , Cambridge, Massachusetts 02138, United States
| | - Anna C Balazs
- Department of Chemical and Petroleum Engineering, University of Pittsburgh , Pittsburgh, Pennsylvania 15261, United States
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Liu Y, Yong X, McFarlin G, Kuksenok O, Aizenberg J, Balazs AC. Designing a gel-fiber composite to extract nanoparticles from solution. SOFT MATTER 2015; 11:8692-8700. [PMID: 26376705 DOI: 10.1039/c5sm01719j] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
The extraction of nanoscopic particulates from flowing fluids is a vital step in filtration processes, as well as the fabrication of nanocomposites. Inspired by the ability of carnivorous plants to use hair-like filaments to entrap species, we use computational modeling to design a multi-component system that integrates compliant fibers and thermo-responsive gels to extract particles from the surrounding solution. In particular, hydrophobic fibers are embedded in a gel that exhibits a lower critical solution temperature (LCST). With an increase in temperature, the gel collapses to expose fibers that self-assemble into bundles, which act as nanoscale "grippers" that bind the particles and draw them into the underlying gel. By varying the relative stiffness of the fibers, the fiber-particle interaction strength and the shear rate in the solution, we identify optimal parameters where the particles are effectively drawn from the solution and remain firmly bound within the gel layer. Hence, the system can be harnessed in purifying fluids and creating novel hybrid materials that integrate nanoparticles with polymer gels.
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Affiliation(s)
- Ya Liu
- Chemical Engineering Department, University of Pittsburgh, Pittsburgh, PA 15261, USA.
| | - Xin Yong
- Department of Mechanical Engineering, Binghamton University, State University of New York, Binghamton, NY 13902-6000, USA
| | - Gerald McFarlin
- Chemical Engineering Department, University of Pittsburgh, Pittsburgh, PA 15261, USA.
| | - Olga Kuksenok
- Chemical Engineering Department, University of Pittsburgh, Pittsburgh, PA 15261, USA.
| | - Joanna Aizenberg
- Wyss Institute for Biologically Inspired Engineering, Department of Chemistry and Chemical Biology, and School of Engineering and Applied Science, Harvard, Cambridge, MA 02138, USA
| | - Anna C Balazs
- Chemical Engineering Department, University of Pittsburgh, Pittsburgh, PA 15261, USA.
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