Regulated Behavior in Living Cells with Highly Aligned Configurations on Nanowrinkled Graphene Oxide Substrates: Deep Learning Based on Interplay of Cellular Contact Guidance.

Micro-/nanotopographical cues have emerged as a practical and promising strategy for controlling cell fate and reprogramming, which play a key role as biophysical regulators in diverse cellular processes and behaviors. Extracellular biophysical factors can trigger intracellular physiological signaling via mechanotransduction and promote cellular responses such as cell adhesion, migration, proliferation, gene/protein expression, and differentiation. Here, we engineered a highly ordered nanowrinkled graphene oxide (GO) surface via the mechanical deformation of an ultrathin GO film on an elastomeric substrate to observe specific cellular responses based on surface-mediated topographical cues. The ultrathin GO film on the uniaxially prestrained elastomeric substrate through self-assembly and subsequent compressive force produced GO nanowrinkles with periodic amplitude. To examine the acute cellular behaviors on the GO-based cell interface with nanostructured arrays of wrinkles, we cultured L929 fibroblasts and HT22 hippocampal neuronal cells. As a result, our developed cell-culture substrate obviously provided a directional guidance effect. In addition, based on the observed results, we adapted a deep learning (DL)-based data processing technique to precisely interpret the cell behaviors on the nanowrinkled GO surfaces. According to the learning/transfer learning protocol of the DL network, we detected cell boundaries, elongation, and orientation and quantitatively evaluated cell velocity, traveling distance, displacement, and orientation. The presented experimental results have intriguing implications such that the nanotopographical microenvironment could engineer the living cells' morphological polarization to assemble them into useful tissue chips consisting of multiple cell types.

Rotating Cylinder-Assisted Nanoimprint Lithography for Enhanced Chemisorbable Filtration Complemented by Molecularly Imprinted Polymers.

Rotating cylindrical stamp-based nanoimprint technique has many advantages, including the continuous fabrication of intriguing micro/nanostructures and rapid pattern transfer on a large scale. Despite these advantages, the previous nanoimprint lithography has rarely been used for producing sophisticated nanoscale patterns on a non-planar substrate that has many extended applications. Here, the simple integration of nanoimprinting process with a help of a transparent stamp wrapped on the cylindrical roll and UV optical source in the core to enable high-throughput pattern transfer, particularly on a fabric substrate is demonstrated. Moreover, as a functional resin material, this innovative strategy involves a synergistic approach on the synthesis of molecularly imprinted polymer, which are spatially organized free-standing perforated nanostructures such as nano/microscale lines, posts, and holes patterns on various woven or nonwoven blank substrates. The proposed materials can serve as a self-encoded filtration medium for selective separation of formaldehyde molecules. It is envisioned that the combinatorial fabrication process and attractive material paves the way for designing next-generation separation systems in use to capture industrial or household toxic substances.