Spontaneous Additive Nanopatterning from Solution Route Using Selective Wetting.

Nanopatterns of functional materials have successfully led innovations in a wide range of fields, but further exploration of their full potential has often been limited because of complex and cost-inefficient patterning processes. We here propose an additive nanopatterning process of functional materials from solution route using selective wetting phenomenon. The proposed process can produce nanopatterns as narrow as 150 nm with high yield over large area at ultrahigh process speed, that is, the speed of solution dragging, of up to ca. 4.6 m·min-1. The process is highly versatile that it can utilize a wide range of solution materials, control vertical structures including pattern thickness and multistacks, and produce nanopatterns on various substrates with emerging form factors such as foldability and disposability. The solution patterning in nanoscale by selective wetting is enabled by corresponding surface energy patterns in high contrast that are achieved by one-step imprinting onto hydrophobic/hydrophilic bilayers. The mechanisms and control parameters for the solution patterning are revealed by fluid-dynamic simulation. With the aforementioned advantages, we demonstrate 25 400 pixel-per-inch light-emitting pixel arrays and a plasmonic color filter of 10 cm × 10 cm area on a plastic substrate as potential applications.

Evaluation of the effects of the combination of autologous mesenchymal stem cells and platelet-rich plasma on structural bone allograft healing.

In this study, we evaluated the efficacy of the combination of autologous mesenchymal stem cells (MSCs) and platelet-rich plasma (PRP) for enhancing structural allogenic bone graft healing in rabbits. For these experiments segmental bone defects (1.5-2 cm) were generated on femoral diaphysis of New Zealand white rabbits and reconstructed via structural allogenic bone grafting and additional intramedullary nail fixation. The structural allografts were subsequently wrapped with Gelfoam containing autologous MSCs and PRP, or PRP alone (control). Grafted periosteal tissues were harvested at 4, 8, and 12 weeks post-implantation and subjected to plain radiographic and, histological, as well as real-time quantitative reverse transcription-PCR analysis of bone morphogenic protein (BMP)-2, BMP-4, BMP-7, receptor activator of nuclear factor-kappa B ligand (RANKL), and vascular endothelial growth factor (VEGF) expression. Compared to those in the control group, the animals in the experimental group exhibited significantly higher Taira radiographic scores at 4 and 12 weeks after surgery, as well as callus formation. Likewise, these animals exhibited increases in BMP-4 production at 4 weeks, RANKL production at 4 and 12 weeks, and BMP-2, BMP-7, and VEGF production at 4, 8, and 12 weeks. Together, these data suggest that the administration of autologous MSCs and PRP resulted in enhanced healing of structural allogenic bone grafts compared to PRP alone. As such, this combination might comprise an ideal therapy for improving the clinical outcomes of structural allografts.

Fabrication of high aspect ratio nanogrid transparent electrodes via capillary assembly of Ag nanoparticles.

In this report, we describe the fabrication of periodic Ag nanogrid electrodes by capillary assembly of silver nanoparticles (AgNPs) along patterned nanogrid templates. By assembling the AgNPs into these high-aspect-ratio nanogrid patterns, we can obtain high-aspect-ratio nanogratings, which can overcome the inherent trade-off between the optical transmittance and the sheet resistance of transparent electrodes. The junction resistance between the AgNPs is effectively reduced by photochemical welding and post-annealing. The fabricated high-aspect-ratio nanogrid structure with a line width of 150 nm and a height of 450 nm has a sheet resistance of 15.2 Ω sq(-1) and an optical transmittance of 85.4%.