The energy density of Li-ion batteries can be increased if graphitic anodes are replaced with nanostructured Si-based materials. Design efficient Si requires a better fundamental understanding the possible changes in Si-Li alloy morphology during cycling. Here we propose simple elastoplastic model to predict morphological upon electrochemical reaction Li confined geometry, such as pore carbon nanotube (CNT). Our experiments CNTs having inner coatings different thicknesses confirmed...

We use a coarse-grained numerical simulation to design synthetic membrane with stable pores that can be controllably opened and closed. Specifically, we dissipative particle dynamics probe the interactions between lipid bilayer membranes nanoparticles. The particles are nanoscopic Janus beads comprise both hydrophobic hydrophilic portions. demonstrate when rips forms hole due an external stress, these nanoparticles diffuse edge of form pore, which persists after stress is released. Once...

Inertial effect of a flowing fluid, often complicating factor in hydrodynamics, offers way to high-purity, high-throughput shape-based separation manmade particles or biological cells microfluidic channels.

Abnormal cell mechanical stiffness can point to the development of various diseases including cancers and infections. We report a new microfluidic technique for continuous separation utilizing variation in stiffness. use channel decorated by periodic diagonal ridges that compress flowing cells rapid succession. The compression combination with secondary flows ridged translates each perpendicular axis proportion its demonstrate physical principle sorting mechanism show our approach be...

Using three-dimensional computer simulations, we examine hovering aerodynamics of flexible planar wings oscillating at resonance. We model as tilted elastic plates whose sinusoidal plunging motion is imposed the plate root. Our simulations reveal that large-amplitude resonance oscillations drastically enhance aerodynamic lift and efficiency low-Reynolds-number plunging. Driven by a simple stroke, generate force comparable to small insects employ very efficient but much more complicated...

Using three-dimensional computer simulations, we study the cross-stream inertial migration of neutrally buoyant deformable particles in a pressure-driven channel flow. The are modeled as elastic shells filled with viscous fluid. We show that equilibrate flow at off-center positions depend on particle size, shell compliance, and viscosity encapsulated These equilibrium positions, however, practically independent magnitude Reynolds number range between 1 100. results our studies can be useful...

Using a mesoscale computational model, we probe the release of nanoparticles and linear macromolecules from hollow microgel capsules that swell deswell in response to external stimuli. Our simulations reveal responsive microcapsules can be effectively utilized for steady pulsatile encapsulated solutes. Swollen gel allow steady, diffusive polymer chains, whereas deswelling causes burst-like discharge solutes driven by an outward flow solvent enclosed within shrinking capsule. We demonstrate...

The enrichment of viable cells is an essential step to obtain effective products for cell therapy. While procedures exist characterize the viability cells, most methods exclude nonviable require use density gradient centrifugation or antibody-based sorting with molecular labels viability. We report a label-free microfluidic technique separate live and dead that exploits differences in cellular stiffness. device uses channel repeated ridges are diagonal respect direction flow. Stiff directed...

Abstract In this article, we investigate the motion of a solid spheroid particle in simple shear flow. Using lattice Boltzmann method, examine individual effects fluid inertia and rotary as well their combination on dynamics trajectory particles at low moderate Reynolds numbers. The single is shown to be dependent number, aspect ratio, initial orientation Stokes number. Spheroids with random orientations are found drift stable orbits influenced by and/or inertia. Specifically, prolate...

Efficient intracellular delivery of target macromolecules remains a major obstacle in cell engineering and other biomedical applications. We discovered unique biophysical phenomenon transient volume exchange by using microfluidics to rapidly repeatedly compress cells. This behavior consists brief, mechanically induced loss followed rapid recovery. harness this for high-throughput, convective large polysaccharides (2000 kDa), particles (100 nm), plasmids while maintaining high viability....

Abstract Cancers consist of a heterogeneous populations cells that may respond differently to treatment through drug-resistant sub-populations. The scarcity these resistant sub-populations makes it challenging understand how counter their resistance. We report label-free microfluidic approach separate cancer treated with chemotherapy into enriched in chemoresistant and chemosensitive based on the differences cellular stiffness. sorting enabled analysis molecular distinctions between...

Organisms use hair-like cilia that beat in a metachronal fashion to actively transport fluid and suspended particles. Metachronal motion emerges due phase difference between beating cycles of neighboring appears as traveling waves propagating along ciliary carpet. In this work, we demonstrate biomimetic artificial capable motion. The are micromachined magnetic thin filaments attached at one end substrate actuated by uniform rotating field. We show the cilium length controls property induce...

By integrating mesoscale models for hydrodynamics and micromechanics, we examine the fluid-driven motion of microcapsules on compliant surfaces. The capsules, modeled as fluid-filled elastic shells, represent polymeric or biological cells. We these capsules flat, mechanically uniform surfaces, patterned surfaces that contain alternating regions hard soft domains, topologically i.e., a corrugated substrate encompasses regular array posts. isolate conditions where topographically can transmit...

Abstract In this work, we introduce anisotropically shaped, ultrathin micro‐ and nano‐capsules fabricated by layer‐by‐layer approach. The original cubic tetrahedral shapes of the template particles were replicated to produce hollow capsules with well‐defined edges. Introducing tannic acid as a component LbL shells resulted in enhanced chemical stability these polymer structures under wide pH range due high p K value. Computational studies demonstrated increased mechanical anisotropic osmotic...

We report a microfluidic approach to separate and enrich mixture of two cell types based on differences in viscoelastic behavior during repeated compressions relaxation events. As proof concept, we demonstrate that variations viscoelasticity affect the flow trajectory one type leukemia line (K562) relation another (HL60) as well healthy leukocytes. These can be utilized sort K562 cells from HL60 The device utilizes periodic, diagonal ridges compress translate laterally perpendicular channel...

We investigate the formation of chains few plasmonic nanoparticles—so-called oligomers—by strain-induced fragmentation linear particle assemblies. Detailed investigations process are conducted by in situ atomic force microscopy and UV–vis–NIR spectroscopy. Based on these experimental results mechanical simulations computed lattice spring model, we propose a mechanism that explains observed decrease chain polydispersity upon increasing strain provides guidelines for tailoring length...

One of the vital functions naturally occurring cilia is fluid transport. Biological use spatially asymmetric strokes to generate a net flow that can be utilized for feeding, swimming, and other functions. Biomimetic synthetic with similar beating useful manipulations in lab-on-chip devices. In this paper, we demonstrate microfluidic pumping by magnetically actuated arranged multi-row arrays. We microchannel loop visualize created ciliary array examine range parameters. show magnetic achieve...

We use three-dimensional computer simulations to examine the free swimming of an elastic plate plunging sinusoidally in a viscous fluid with Reynolds number 250. find that velocity is maximized when swimmer driven near first natural frequency leading larger deformations, and nearly linearly related trailing edge displacement. The maximum performance found at non-resonance frequency. takes place exhibits deformation pattern which transverse displacement swimmer's center mass minimized, turn...

Significance Microgel suspensions are a fascinating class of soft materials comprising compliant colloidal particles that can deform, swell/deswell, and interpenetrate. Understanding the behavior microgels in dense guide design self-healing synthetic with novel mechanical properties facilitate development mechanistic models for biological tissues. We harness mesoscale computer simulations to probe fate during suspension compression show below space-filling deform slightly shrink, whereas...

Using computational modeling, we simulate the 3D movement of actuated cilia in a fluid-filled microchannel. The are modeled as deformable, elastic filaments, and simulations capture complex fluid−structure interactions among these channel walls, surrounding solution. tilted with respect to surface by sinusoidal force that is applied at free ends. We find give rise unidirectional flow system simply altering frequency can controllably switch direction net flow. findings indicate beating,...

We use computational modeling to capture the three-dimensional interactions between oscillating, synthetic cilia and a microscopic particle in fluid-filled microchannel. The are elastic filaments that tethered substrate actuated by sinusoidal force, which is applied their free ends. arranged square pattern, neutrally buoyant initially located these filaments. Our studies reveal that, depending on frequency of beating cilia, can be either driven downward toward or upward expelled into fluid...