Paper-based cell culture platforms have emerged as a promising approach for a myriad of biomedical applications, such as tissue engineering, disease models, cancer research, biotechnology, high-throughput testing, biosensing, and diagnostics. Paper enables the generation of highly flexible, biocompatible, inexpensive, porous, and three-dimensional (3D) constructs and devices. These systems have been used to culture mammalian cells, bacteria, algae, and fungi. Studies have shown that paper is an exceptional material for applications in life sciences, materials sciences, engineering, and medicine. Paper has been employed for creating biomimetic cell culture environments by folding or stacking it into the desired 3D shapes and structures. This review discusses the use of paper-based platforms for cellular applications and provides a diverse range of examples.

Besides graphite and diamond, the solid allotropes of carbon in sp2 and sp3 hybridization, the possible existence of a third allotrope based on the sp-carbon linear chain, the carbyne, has stimulated researchers for a long time. The advent of fullerenes, nanotubes, and graphene has opened new opportunities and nurtured the interest in novel carbon allotropes, including linear structures. The efforts made in this direction produced a number of interesting sp-hybridized carbon molecules and nanostructures in the form of carbon-atom wires. Here we discuss some of the new perspectives opened by the recent advancements in the research on sp-carbon systems.

One-dimensional zinc oxide (ZnO) nanostructure arrays show unique semiconducting, piezoelectric, and wetting properties, and how they interact with cells is critical for their biomedical applications. In this work, we prepare ZnO nanorod arrays (ZnO NRAs) and study their interactions with neonatal rat cardiomyocytes either as a substrate or patch. We find that ZnO NRAs can (1) inhibit cell adhesion and spreading as a substrate and (2) selectively kill underneath cells as a patch. We further identify surface nanomorphology as the dominant factor responsible for the inhibitory effect. These discoveries suggest potential application of ZnO NRAs as a cell inhibitory biointerface.

In this paper new materials and substrate approaches are discussed which have potential to provide (Al)GaN buffers with a better crystal quality, higher critical electrical field, or thickness and have the potential to offer co-integration of GaN switches at different reference potentials, while maintaining lower wafer bow and maintaining complementary metal–oxide semiconductor (CMOS) compatibility. Engineered silicon substrates, silicon on insulator (SOI) and coefficient of thermal expansion (CTE)-matched substrates have been investigated and benchmarked with respect to each other. SOI and CTE-matched offer benefits for scaling to higher voltage, while a trench isolation process combined with an oxide interlayer substrate allows co-integration of GaN components in a GaN-integrated circuit (IC).

Wearable healthcare technologies should be non-invasive, robust to daily activity/environments, easy to use, and comfortable to wear. Flexible substrate devices for biomarker monitoring can contribute to wearable diagnostic applications. Single-target biosensors have extensively been developed for health-monitoring applications; however, recently multiplex biomarker tests have generated clinical interest. Targeting multiple biomarkers in diagnostic systems (wearable or point of care) offers more focused diagnosis and treatment as changes in a single biomarker can be caused by a series of physiologic conditions. This review highlights flexible substrates that have been successfully demonstrated for multiplex biomarker detection with potential for healthcare monitoring.

It is of the uttermost interest to understand the mechanical performance and deformation mechanisms contributing to small-scale plasticity of materials in micro/nanoelectromechanical systems at their service temperatures, which are usually above room temperature. In recent years, high-temperature nanoindentation experiments have emerged as a reliable approach to characterize the deformation behavior of materials at the nano and submicron scale. In this review, we highlight the role of the temperature in nanoindentation response of a wide variety of materials, with a particular focus on the thermally-activated deformation mechanisms in crystalline and non-crystalline materials under the indenter, e.g., dislocation processes, shear transformation zone, and phase transformations. A brief survey of the temperature-dependent nanoindentation elastic modulus, hardness, and creep behavior of materials is also provided. We also discuss experimental methods for correctly measuring the mechanical properties of materials at high temperatures.

Evolving from the oblique-angle deposition method used industrially for the deposition of thin films, the conformal-evaporated-film-by-rotation (CEFR) technique has been successfully applied to replicate surfaces of biologic origin. The CEFR technique is the first step of the Nano4Bio technique, an industrially scalable bioreplication process, the other three steps being electroforming, plasma ashing, and either stamping or casting. These techniques have found optical applications in diverse fields, including forensic science, pest control, and light sources.

Nanomaterials have been proposed as key components in biosensing, imaging, and drug delivery since they offer distinctive advantages over conventional approaches. The unique chemical and physical properties of graphene make it possible to functionalize and develop protein transducers, therapeutic delivery vehicles, and microbial diagnostics. In this study, we evaluate reduced graphene oxide as a potential nanomaterial for quantification of microRNAs including their structural differentiation in vitro in solution and inside intact cells. Our results provide evidence for the potential use of graphene nanomaterials as a platform for developing devices that can be used for microRNA quantitation as biomarkers for clinical applications.

A review of the literature offers an explanation for the large anomalous electro-optic (e.o.) effect reported by Fujiwara et al. in 1994. It is based on the large e.o. coefficient of ordered water at an interface measured in recent years >1000 pm/V. More broadly, the concept of water-based photonics, where water could be a new platform material for devices and systems, is introduced, suggesting that liquid states of matter can allow ready shaping and exploitation of many processes in ways not previously considered. This paper is a commentary on the significance of this new understanding and the broader interest of water in photonics, particularly its consideration as a new platform material.

The aim of current study is to fabricate implantable curcumin embedded gelatin/polylactic acid/curcumin (GL/PLA/Cur) aligned fiber scaffolds by forcespinning®, which might have a potential application in drug delivery and cancer therapy. Fourier Transform Infrared Spectroscopy reveals the hydrogen bonding interactions between GL, PLA, and curcumin. In vitro curcumin drug release from GL/PLA/Cur fiber scaffolds is investigated and sustained release is observed over 15 days. Further, cell viability assay reveals that GL/PLA/Cur aligned fibers show excellent growth of human fibroblast cells. These results strongly suggest that the curcumin bearing GL/PLA/Cur composite fibers may show the potential application in cancer therapy, drug delivery, and wound dressing.

The helium ion microscope (HeIM) holds immense promise for nano-engineering and imaging with scope for in-situ chemical analysis. Here we will examine the potential of secondary electron hyperspectral imaging (SEHI) as a new route to exploring chemical variations in both two and three dimensions. We present a range of early applications in the context of image interpretation in wider materials science and process control in ion beam-based nano-engineering. Necessary steps for SEHI in the HeIM to evolve into a reliable technique which can be fully embedded into nano-engineering workflows are considered.

The inefficiencies of the current pipeline from discovery to clinical approval of drugs demand a surrogate method to indicate adverse drug reactions, e.g. liver damage. Organ-on-chip (OOC) models would be an ideal, rapid, and human-specific alternate, which would render animal testing obsolete. The ground-breaking ability of OOCs and Multi-OOC constructs is the accurate simulation of the in vivo conditions of human organs leading to precise drug screens for cytotoxicity and/or drug efficacy at a faster pace and lesser cost. Here we discuss the innovation, architecture, and the progress of OOCs towards human body-on-a-chip.

Co–Cr alloys, more specifically L605, have superior mechanical properties and high-corrosion resistance, making them suitable materials for cardiovascular application. However, metallic materials for biomedical applications require finely tuned surface properties to improve the material behavior in a physiological environment. Oxygen plasma immersion ion implantation was performed on an L605 alloy, after an electropolishing pre-treatment. The oxidized layer was found to be rich in Co and O, it did not show any trace of Cr, and resulted in nanostructured. The corrosion properties were profoundly changed. Endothelial cells showed high viability after 7 days of contact with some modified surfaces.

In this work, we report on the adhesion of HCT116 (human colon carcinoma cells) cultured on nanofibrillar polymethylmethacrylate (PMMA) and SU-8 micropillars substrates. Both surfaces enabled a good cell proliferation and promoted the formation of adherent interconnections with the fabricated nano- and microstructures. The three-dimensional immunofluorescence confocal characterization of the cells on nanotextured PMMA highlighted the expression of well-spread F-actin cytoskeletal networks as well as the presence of focal adhesions. This study provides thus interesting perspectives for further investigations on the force/adhesion mechanisms related to cancer cell growth and proliferation.

Properly driving protein interactions with solid surfaces play a very important role in many natural processes, stimulating a great interest for the design of new biomaterials and medical devices. Despite the progress in this field, many further upgrades have to be achieved to better exploit the protein driving, in terms of control of amounts and conformation of the adsorbing proteins. In this paper, new biocompatible amino acid–calix[4]crown-5 bilayers were built as nano-templating surfaces, hosting a controlled number of anchoring sites, able to immobilize proteins in well-defined quantity, and the evaluated footprint data support the idea of oriented protein on analyzed substrates. The efficiency of the setup was tested for the particular case of antibacterial lysozyme adsorption on biocompatible surfaces.

Atomic clusters attached to a low-dimensional system, called Fano defects, produce rich wave interferences. In this work, we analytically found an enhanced thermoelectric figure-of-merit (ZT) in periodic atomic chains with Fano defects, compared with those without such defects. We further study self-assembled DNA-like systems with periodic and quasiperiodically placed Fano defects by using a real-space renormalization method developed for the Kubo–Greenwood formula, in which tight-binding and Born models are respectively used for the electric and lattice thermal conductivities. The results reveal that the quasiperiodicity could be another ZT-improving factor, whose long-range disorder inhibits low-frequency acoustic phonons insensitive to local defects.

Nitrogen-doped graphene (N-G) is a promising non-platinum group metal catalyst for oxygen reduction reaction. A new N-G/metal organic framework (MOF) catalyst is derived by the modification of MOF on N-G catalysts to enhance the electrochemical performance of N-G by increasing the surface area and porosity in this paper. The characterization confirmed that the Brunauer–Emmett–Teller surface areas of N-G/MOF catalysts are 13–66 times larger than the original N-G catalyst. The highest current density (5.02 mA/cm2) and electron transfer number (3.93) of N-G/MOFs are higher than the N-G catalyst. The current density of N-G/MOF catalyst is even higher than 10 wt% Pt/C catalyst.

We report results of the studies relating to the development of the emerging nanostructured molybdenum trioxide (nMoO3)-based biocompatible label-free biosensing platform for breast cancer detection. The structural and morphological studies of the synthesized nMoO3 nanorods were investigated by XRD, SEM, X-ray photoelectron spectroscopic, and TEM techniques. This biocompatible one-dimensional (1D) nMoO3-based biosensing platform exhibited high sensitivity (0.904 µAmL/ng/cm2), wide linear detection range (2.5–110 ng/mL), and a lower detection limit as 2.47 ng/mL toward human epidermal growth factor receptor-2 detection. The results obtained using this sensor platform on serum samples of breast cancer patients were validated using ELISA.

We report on reliability testing of vertical GaN (v-GaN) devices under continuous switching conditions of 500, 750, and 1000 V. Using a modified double-pulse test circuit, we evaluate 1200 V-rated v-GaN PiN diodes fabricated by Avogy. Forward current–voltage characteristics do not change over the stress period. Under the reverse bias, the devices exhibit an initial rise in leakage current, followed by a slower rate of increase with further stress. The leakage recovers after a day's relaxation which suggests that trapping of carriers in deep states is responsible. Overall, we found the devices to be robust over the range of conditions tested.