Novel Concept of Micro Patterned Micro Titer Plates Fabricated via UV-NIL for Automated Neuronal Cell Assay Read-Out

Continuous roller nanoimprinting: next generation lithography

Nanoimprint lithography (NIL) is a cost-effective and high-throughput technique for replicating nanoscale structures that does not require expensive light sources for advanced photolithography equipment. NIL overcomes the limitations of light diffraction or beam scattering in traditional photolithography and is suitable for replicating nanoscale structures with high resolution. Roller nanoimprint lithography (R-NIL) is the most common NIL technique benefiting large-scale, continuous, and efficient industrial production. In the past two decades, a range of R-NIL equipment has emerged to meet the industrial needs for applications including biomedical devices, semiconductors, flexible electronics, optical films, and interface functional materials. R-NIL equipment has a simple and compact design, which allows multiple units to be clustered together for increased productivity. These units include transmission control, resist coating, resist curing, and imprinting. This critical review summarizes the hitherto R-NIL processes, their typical technical problems, and corresponding solutions and gives guidelines for developing advanced R-NIL equipment.

The Bumpy Road to Stem Cell Therapies: Rational Design of Surface Topographies to Dictate Stem Cell Mechanotransduction and Fate

Cells sense and respond to a variety of physical cues from their surrounding microenvironment, and these are interpreted through mechanotransductive processes to inform their behavior. These mechanisms have particular relevance to stem cells, where control of stem cell proliferation, potency, and differentiation is key to their successful application in regenerative medicine. It is increasingly recognized that surface micro- and nanotopographies influence stem cell behavior and may represent a powerful tool with which to direct the morphology and fate of stem cells. Current progress toward this goal has been driven by combined advances in fabrication technologies and cell biology. Here, the capacity to generate precisely defined micro- and nanoscale topographies has facilitated the studies that provide knowledge of the mechanotransducive processes that govern the cellular response as well as knowledge of the specific features that can drive cells toward a defined differentiation outcome. However, the path forward is not fully defined, and the "bumpy road" that lays ahead must be crossed before the full potential of these approaches can be fully exploited. This review focuses on the challenges and opportunities in applying micro- and nanotopographies to dictate stem cell fate for regenerative medicine. Here, key techniques used to produce topographic features are reviewed, such as photolithography, block copolymer lithography, electron beam lithography, nanoimprint lithography, soft lithography, scanning probe lithography, colloidal lithography, electrospinning, and surface roughening, alongside their advantages and disadvantages. The biological impacts of surface topographies are then discussed, including the current understanding of the mechanotransductive mechanisms by which these cues are interpreted by the cells, as well as the specific effects of surface topographies on cell differentiation and fate. Finally, considerations in translating these technologies and their future prospects are evaluated.

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.