Production of Lipid Constructs by Design via Three-Dimensional Nanoprinting.

Atomic force microscopy (AFM) in conjunction with microfluidic delivery was utilized to produce three-dimensional (3D) lipid structures following a custom design. While AFM is well-known for its spatial precision in imaging and 2D nanolithography, the development of AFM-based nanotechnology into 3D nanoprinting requires overcoming the technical challenges of controlling material delivery and interlayer registry. This work demonstrates the concept of 3D nanoprinting of amphiphilic molecules such as 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC).

Mechanical Cues for Triggering and Regulating Cellular Movement Selectively at the Single-Cell Level.

Cell motility plays important roles in many biophysical and physiological processes ranging from in vitro biomechanics, wound healing, to cancer metastasis. This work introduces a new means to trigger and regulate motility individually using transient mechanical stimulus applied to designated cells. Using BV2 microglial cells, our investigations indicate that motility can be reproducibly and reliably initiated using mechanical compression of the cells.

Impact of Surface Polarity on Lipid Assembly under Spatial Confinement.

Molecular dynamics (MD) simulations in the MARTINI model are used to study the assembly of 1-palmitoyl-2-oleoylphosphatidylcholine (POPC) molecules under spatial confinement, such as during solvent evaporation from ultrasmall (femtoliter quantity) droplets. The impact of surface polarity on molecular assembly is discussed in detail. To the best of our knowledge, this work represents the first of its kind.

Efficacy of simple continuum models for diverse granular intrusions.

Granular intrusion is commonly observed in natural and human-made settings. Unlike typical solids and fluids, granular media can simultaneously display fluid-like and solid-like characteristics in a variety of intrusion scenarios. This multi-phase behavior increases the difficulty of accurately modeling these and other yielding (or flowable) materials.