Surface Functionalization of 3D-Printed Scaffolds with Seed-Assisted Hydrothermally Grown ZnO Nanoarrays for Bone Tissue Engineering.

Bioactive metal-based nanostructures, particularly zinc oxide (ZnO), are promising materials for bone tissue engineering. However, integrating them into 3D-printed polymers using traditional blending methods reduces the cell performance. Alternative surface deposition techniques often require extreme conditions that are unsuitable for polymers.

Challenges of Positive Airway Pressure Treatment for Patients With Obstructive Sleep Apnea at a Veterans Medical Center.

Objective: Positive airway pressure (PAP) compliance is important in treating obstructive sleep apnea. Previous studies have suggested that patients with economic burdens, discomfort using machines, and insufficient education have difficulty tolerating PAP machines. This study explored the factors affecting short-term adherence to PAP in a veterans medical center.

Rapid Electrohydrodynamic-Driven Pattern Replication over a Large Area via Ultrahigh Voltage Pulses.

Despite the prospects of electrohydrodynamic instability patterning (EHIP), poor process parameter controllability is a significant challenge in uniform large-scale nanopatterning. Herein, we introduce a EHIP process using an ultrahigh electric field (>10 V/m) to effectively accelerate the pattern growth evolution. Owing to the strong dependence on a temporal parameter (1/τ) of the field strength, our method not only reduces the completion time of pattern growth but also overcomes critical parametric restrictions on the pattern replication, thereby enhancing the replicated pattern quality in three dimensions.

Conductive Thread-Based Immunosensor for Pandemic Influenza A (H1N1) Virus Detection.

Infectious agents such as viruses pose significant threats to human health, being transmitted via direct contact as well as airborne transmission without direct contact, thus requiring rapid detection to prevent the spread of infectious diseases. In this study, we developed a conductive thread-based immunosensor (CT-IS), a biosensor to easily detect the presence of airborne viruses. CT-IS utilizes an antibody that specifically recognizes the HA protein of the pandemic influenza A (pH1N1) virus, which is incorporated into the conductive thread.

Real-time and label-free biosensing using moiré pattern generated by bioresponsive hydrogel.

Bioresponsive hydrogels are smart materials that respond to various external stimuli and exhibit great potential as biosensors owing to their capability of real-time and label-free detection. Here, we propose a sensing platform based on bioresponsive hydrogels, employing the concept of moiré patterns. Two sets of line patterns with different pitch sizes are prepared; a hydrogel grating whose pitch size changes according to external stimuli and a reference grating with constant pitch size.

High diopter spectacle using a flexible Fresnel lens with a combination of grooves.

In this study, the Fresnel lens was investigated as a potential candidate for vision correction in patients with myopia. A few previous studies have suggested this idea; however, Fresnel lenses are limited by their aesthetics and quality. Therefore, we designed a combination of Fresnel lens grooves with a constant height and pitch of 13 µm and 0.

Fabrication of Nanostructures on a Large-Area Substrate with a Minimized Stitch Error Using the Step-and-Repeat Nanoimprint Process.

Nanoimprint lithography (NIL) is suitable for achieving high uniformity and mass production. However, in conventional NIL, a stamp suitable for the substrate size is required to increase the substrate size. To address this issue, we fabricated nanostructures on a large-area substrate using step-and-repeat NIL after making a small stamp.

Parametric scheme for rapid nanopattern replication electrohydrodynamic instability.

Electrohydrodynamic (EHD) instability patterning exhibits substantial potential for application as a next-generation lithographic technique; nevertheless, its development continues to be hindered by the lack of process parameter controllability, especially when replicating sub-microscale pattern features. In this paper, a new parametric guide is introduced. It features an expanded range of valid parameters by increasing the pattern growth velocity, thereby facilitating reproducible EHD-driven patterning for perfect nanopattern replication.

Hierarchically Porous, Laser-Pyrolyzed Carbon Electrode from Black Photoresist for On-Chip Microsupercapacitors.

We report a laser-pyrolyzed carbon (LPC) electrode prepared from a black photoresist for an on-chip microsupercapacitor (MSC). An interdigitated LPC electrode was fabricated by direct laser writing using a high-power carbon dioxide (CO) laser to simultaneously carbonize and pattern a spin-coated black SU-8 film. Due to the high absorption of carbon blacks in black SU-8, the laser-irradiated SU-8 surface was directly exfoliated and carbonized by a fast photo-thermal reaction.

Microfluidic device for one-step detection of breast cancer-derived exosomal mRNA in blood using signal-amplifiable 3D nanostructure.

Metastasis attributed to approximately 90% of cancer-related deaths; hence, the detection of metastatic tumor-derived components in the blood assists in determining cancer recurrence and patient survival. Microfluidic-based sensors facilitate analysis of small fluid volumes and represent an accurate, rapid, and user-friendly method of field diagnoses. In this study, we have developed a microfluidic chip-based exosomal mRNA sensor (exoNA-sensing chip) for the one-step detection of exosomal ERBB2 in the blood by integrating a microfluidic chip and 3D-nanostructured hydrogels.

Highly Sensitive and Reliable microRNA Detection with a Recyclable Microfluidic Device and an Easily Assembled SERS Substrate.

Surface-enhanced Raman spectroscopy (SERS) detection in microfluidics is an interesting topic because of its high sensitivity, miniaturization, and ability to perform online detection. However, the difficulties in generating SERS-based microfluidic devices with uniform signal reproducibility and high sensitivity have hindered their widespread application. In addition, the recyclability of the SERS-based microfluidic devices can contribute to their broad commercialization, but the possible contamination in the detection area and cumbersome cleaning procedures remain a challenge.

Biomimetic Nanopillar-Based Biosensor for Label-Free Detection of Influenza A Virus.

Since the first emergence of influenza viruses, they have caused the flu seasonally worldwide. Precise detection of influenza viruses is required to prevent the spreading of the disease. Herein, we developed an optical biosensor using peptide-immobilized nanopillar structures for the label-free detection of influenza viruses.

Fog Collection Based on Secondary Electrohydrodynamic-Induced Hybrid Structures with Anisotropic Hydrophilicity.

The outcomes of the study of plant surfaces, such as rice leaves or bamboo leaves, have led to extensive efforts being devoted to fabricating anisotropic arrays of micro/nanoscale features for exploring anisotropic droplet spreading. Nonetheless, precise engineering of the density and continuity of three-phase contact lines for anisotropic wetting remains a significant challenge without resorting to chemical modifications and costly procedures. In this work, we investigated secondary electrohydrodynamic instability in polymer films for producing secondary nanosized patterns between the micrometer-sized grooves by controlling the timescale parameter, 1/τ (>10 s).

Three-Dimensional Printable Hydrogel Using a Hyaluronic Acid/Sodium Alginate Bio-Ink.

Bio-ink properties have been extensively studied for use in the three-dimensional (3D) bio-printing process for tissue engineering applications. In this study, we developed a method to synthesize bio-ink using hyaluronic acid (HA) and sodium alginate (SA) without employing the chemical crosslinking agents of HA to 30% (/). Furthermore, we evaluated the properties of the obtained bio-inks to gauge their suitability in bio-printing, primarily focusing on their viscosity, printability, and shrinkage properties.

Integrated, Automated, Fast PCR System for Point-Of-Care Molecular Diagnosis of Bacterial Infection.

We developed an integrated PCR system that performs automated sample preparation and fast polymerase chain reaction (PCR) for application in point-of care (POC) testing. This system is assembled from inexpensive 3D-printing parts, off-the-shelf electronics and motors. Molecular detection requires a series of procedures including sample preparation, amplification, and fluorescence intensity analysis.

Selective Transfer of Light-Emitting Diodes onto a Flexible Substrate via Laser Lissajous Scanning.

As the light-emitting diode (LED) size gradually decreases, it is difficult to conventionally transfer an LED onto a donor substrate. In this paper, we propose a print transfer method that selectively transfers an LED onto a UV release tape, i.e.

Peptidoglycan-Binding Protein Metamaterials Mediated Enhanced and Selective Capturing of Gram-Positive Bacteria and Their Specific, Ultra-Sensitive, and Reproducible Detection via Surface-Enhanced Raman Scattering.

Biological metamaterials with a specific size and spacing are necessary for developing highly sensitive and selective sensing systems to detect hazardous bacteria in complex solutions. Herein, the construction of peptidoglycan-binding protein (PGBP)-based metamaterials to selectively capture Gram-positive cells with high efficacy is reported. Nanoimprint lithography was used to generate a nanohole pattern as a template, the inside of which was modified with nickel(II)-nitrilotriacetic acid (Ni-NTA).

A Lipid-Nanopillar-Array-Based Immunosorbent Assay.

Since infectious diseases, particularly viral infections, have threatened human health and caused huge economical losses globally, a rapid, sensitive, and selective virus detection platform is highly demanded. Enzyme-linked immunosorbent assay (ELISA) with flat solid substrates has been dominantly used in detecting whole viruses for its straightforwardness and simplicity in assay protocols, but it often suffers from limited sensitivity, poor quantification range, and a time-consuming assay procedure. Here, a lipid-nanopillar-array-based immunosorbent assay (LNAIA) is developed with a nanopillar-supported lipid bilayer substrate with fluorophore-modified antibodies for rapid, sensitive, and quantitative detection of viruses.

System for Fabrication of Large-Area Roll Molds by Step-and-Repeat Liquid Transfer Imprint Lithography.

The effective production of nanopatterned films generally requires a nanopatterned roll mold with a large area. We report on a novel system to fabricate large-area roll molds by recombination of smaller patterned areas in a step-and-repeat imprint lithography process. The process is accomplished in a method similar to liquid transfer imprint lithography (LTIL).

An electrophoretic DNA extraction device using a nanofilter for molecular diagnosis of pathogens.

Rapid and efficient nucleic acid (NA) extraction and concentration are required for point-of-care analysis in order to prevent an epidemic/pandemic disease outbreak. Typical silica-based NA extraction methods have limitations such as being time-consuming, requiring human intervention, and resulting in a low recovery yield. In this study, we have developed a pathogenic DNA extraction device based on electrokinetic separation incorporated with a silicon nitride (SiNx) nanofilter, which expedites the DNA extraction procedure with advantages of being convenient, efficient, and inexpensive.

Direct electrophoretic microRNA preparation from clinical samples using nanofilter membrane.

A method to directly collect negatively charged nucleic acids, such as DNA and RNA, in the biosamples simply by applying an electric field in between the sample and collection buffer separated by the nanofilter membrane is proposed. The nanofilter membrane was made of low-stress silicon nitride with a thickness of 100 nm, and multiple pores were perforated in a highly arranged pattern using nanoimprint technology with a pore size of 200 nm and a pore density of 7.22 × 10/cm.

Fabrication and Characterization of Bioresorbable Drug-coated Porous Scaffolds for Vascular Tissue Engineering.

Bioresorbable polymers have been studied for several decades as attractive candidates for promoting the advancement of medical science and bio-technology in modern society. In particular, with a well-defined architecture, bioresorbable polymers have prominent advantages over their bulk counterparts for applications in biomedical and implant devices, such as cell delivery, scaffolds for tissue engineering, and hydrogels as well as in the pharmaceutical fields. Biocompatible implant devices based on bioresorbable materials (for instance, bioresorbable polymers that combine the unique advantages of biocompability and easy handling) have emerged as a highly active field due to their promising applications in artificial implant systems and biomedical devices.

Formation of Interstitial Hot-Spots Using the Reduced Gap-Size between Plasmonic Microbeads Pattern for Surface-Enhanced Raman Scattering Analysis.

To achieve an effective surface-enhanced Raman scattering (SERS) sensor with periodically distributed "hot spots" on wafer-scale substrates, we propose a hybrid approach combining physical nano-imprint lithography and a chemical deposition method to form a silver microbead array. Nano-imprint lithography (NIL) can lead to mass-production and high throughput, but is not appropriate for generating strong "hot-spots." However, when we apply electrochemical deposition to an NIL substrate and the reaction time was increased to 45 s, periodical "hot-spots" between the microbeads were generated on the substrates.

Large area patterning of residue-free metal oxide nanostructures by liquid transfer imprint lithography.

One-dimensional (1D) and three-dimensional (3D) residue-free metal oxide patterns are directly fabricated over large areas using liquid transfer imprint lithography (LTIL) with an ultraviolet-curable metal oxide precursor resist. A 1D line or pillar array of metal oxides nano-patterns without a residual layer is formed by LTIL and annealing processes. A 3D layer-by-layer nanomesh structure is successfully constructed by repeating the LTIL method without a complex etching process.

Cuvette-based microfluidic device integrated with nanostructures for measuring dual Localized Surface Plasmon Resonance (LSPR) signals.

A spectrophotometer that uses a localized surface plasmon resonance phenomenon is a powerful measurement tool in the biotechnology and bioanalysis fields. We propose a novel cuvette design type that can be used for universal spectrophotometers. The novel cuvette design needs a few l reagent for measuring, and also two chips for measurement can be loaded and measured at the same time.