Metallosupramolecular grid complexes (hereafter referred to as metallogrids) are well-defined oligonuclear metal ion complexes involving essentially planar arrays of the metal ions sited at the ...points of intersection of square or rectangular metallogrids and possess a variety of interesting optical, electronic, magnetic and supramolecular properties. Herein I aim to give the reader an overview of the synthesis, properties and potential for a variety of high-tech applications of metallogrids.
Metallosupramolecular grid complexes (hereafter referred to as metallogrids) are well-defined oligonuclear metal ion complexes involving essentially planar arrays of the metal ions sited at the points of intersection of square or rectangular metallogrids and possess a variety of interesting optical, electronic, magnetic and supramolecular properties.
Shape‐memory polymers (SMPs) are morphologically responsive materials with potential for a variety of biomedical applications, particularly as devices for minimally invasive surgery and the delivery ...of therapeutics and cells for tissue engineering. A brief introduction to SMPs is followed by a discussion of the current progress toward the development of SMP‐based biomaterials for clinically relevant biomedical applications.
Stimuli‐responsive shape‐memory polymer‐based materials have great potential for a variety of biomedical applications. Their development toward use as functional biomedical devices for drug delivery, minimally invasive surgery and tissue engineering are discussed, particularly with a view to their progress toward clinical relevance.
Plants produce a variety of high-value chemicals (e.g., secondary metabolites) which have a plethora of biological activities, which may be utilised in many facets of industry (e.g., agrisciences, ...cosmetics, drugs, neutraceuticals, household products, etc.). Exposure to various different environments, as well as their treatment (e.g., exposure to chemicals), can influence the chemical makeup of these plants and, in turn, which chemicals will be prevalent within them. Essential oils (EOs) usually have complex compositions (>300 organic compounds, e.g., alkaloids, flavonoids, phenolic acids, saponins and terpenes) and are obtained from botanically defined plant raw materials by dry/steam distillation or a suitable mechanical process (without heating). In certain cases, an antioxidant may be added to the EO (EOs are produced by more than 17,500 species of plants, but only ca. 250 EOs are commercially available). The interesting bioactivity of the chemicals produced by plants renders them high in value, motivating investment in their production, extraction and analysis. Traditional methods for effectively extracting plant-derived biomolecules include cold pressing and hydro/steam distillation; newer methods include solvent/Soxhlet extractions and sustainable processes that reduce waste, decrease processing times and deliver competitive yields, examples of which include microwave-assisted extraction (MAE), ultrasound-assisted extraction (UAE), subcritical water extraction (SWE) and supercritical CO2 extraction (scCO2). Once extracted, analytical techniques such as chromatography and mass spectrometry may be used to analyse the contents of the high-value extracts within a given feedstock. The bioactive components, which can be used in a variety of formulations and products (e.g., displaying anti-aging, antibacterial, anticancer, anti-depressive, antifungal, anti-inflammatory, antioxidant, antiparasitic, antiviral and anti-stress properties), are biorenewable high-value chemicals.
A sacrificial templating process using lithographically printed minimal surface structures allows complex de novo geometries of delicate hydrogel materials. The hydrogel scaffolds based on cellulose ...and chitin nanofibrils show differences in terms of attachment of human mesenchymal stem cells, and allow their differentiation into osteogenic outcomes. The approach here serves as a first example toward designer hydrogel scaffolds viable for biomimetic tissue engineering.
Diabetes is a group of metabolic conditions resulting in high blood sugar levels over prolonged periods that affects hundreds of millions of patients worldwide. Measuring glucose concentration ...enables patient-specific insulin therapy, and is essential to reduce the severity of the disease, potential complications, and related mortalities. Recent advances and developments in smartphone-based colorimetric glucose detection systems are discussed in this review. The importance of glucose monitoring, data collection, transfer, and analysis,
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non-invasive/invasive methods is highlighted. The review also presents various approaches using 3D-printed materials, screen-printed electrodes, polymer templates, designs allowing multiple glucose analysis, bioanalytes and/or nanostructures for glucose detection. The positive effects of advances in improving the performance of smartphone-based platforms are introduced along with future directions and trends in the application of emerging technologies in smartphone-based diagnostics.
Smartphone-based colorimetric glucose detection methods have the advantageous combination of software and hardware systems that will revolutionize the concept of smartphone-based platforms from glucose measurement to personal health management.
A number of animals have evolved to produce silk-based composite materials for a variety of task-specific applications. The review initially focuses on the composite structure of silk fibers produced ...naturally by silkworms and spiders, followed by the preparation and applications of man-made composite materials (including fibers, films, foams, gels and particulates) incorporating silk proteins in combination with other polymers (both natural and synthetic) and/or inorganic particles.
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Conductive and electroactive polymers have the potential to enhance engineered cardiac tissue function. In this study, an interpenetrating network of the electrically-conductive ...polymer polypyrrole (PPy) was grown within a matrix of flexible polycaprolactone (PCL) and evaluated as a platform for directing the formation of functional cardiac cell sheets. PCL films were either treated with sodium hydroxide to render them more hydrophilic and enhance cell adhesion or rendered electroactive with PPy grown via chemical polymerization yielding PPy–PCL that had a resistivity of 1.0±0.4kΩcm, which is similar to native cardiac tissue. Both PCL and PPy–PCL films supported cardiomyocyte attachment; increasing the duration of PCL pre-treatment with NaOH resulted in higher numbers of adherent cardiomyocytes per unit area, generating cell densities which were more similar to those on PPy–PCL films (1568±126cellsmm−2, 2880±439cellsmm−2, 3623±456cellsmm−2 for PCL with 0, 24, 48h of NaOH pretreatment, respectively; 2434±166cellsmm−2 for PPy–PCL). When cardiomyocytes were cultured on the electrically-conductive PPy–PCL, more cells were observed to have peripheral localization of the gap junction protein connexin-43 (Cx43) as compared to cells on NaOH-treated PCL (60.3±4.3% vs. 46.6±5.7%). Cx43 gene expression remained unchanged between materials. Importantly, the velocity of calcium wave propagation was faster and calcium transient duration was shorter for cardiomyocyte monolayers on PPy–PCL (1612±143μm/s, 910±63ms) relative to cells on PCL (1129±247μm/s, 1130±20ms). In summary, PPy–PCL has demonstrated suitability as an electrically-conductive substrate for culture of cardiomyocytes, yielding enhanced functional properties; results encourage further development of conductive substrates for use in differentiation of stem cell-derived cardiomyocytes and cardiac tissue engineering applications.
Current conductive materials for use in cardiac regeneration are limited by cytotoxicity or cost in implementation. In this manuscript, we demonstrate for the first time the application of a biocompatible, conductive polypyrrole–polycaprolactone film as a platform for culturing cardiomyocytes for cardiac regeneration. This study shows that the novel conductive film is capable of enhancing cell–cell communication through the formation of connexin-43, leading to higher velocities for calcium wave propagation and reduced calcium transient durations among cultured cardiomyocyte monolayers. Furthermore, it was demonstrated that chemical modification of polycaprolactone through alkaline-mediated hydrolysis increased overall cardiomyocyte adhesion. The results of this study provide insight into how cardiomyocytes interact with conductive substrates and will inform future research efforts to enhance the functional properties of cardiomyocytes, which is critical for their use in pharmaceutical testing and cell therapy.
Carbon-based conductive and electroactive materials (e.g., derivatives of graphene, fullerenes, polypyrrole, polythiophene, polyaniline) have been studied since the 1970s for use in a broad range of ...applications. These materials have electrical properties comparable to those of commonly used metals, while providing other benefits such as flexibility in processing and modification with biologics (e.g., cells, biomolecules), to yield electroactive materials with biomimetic mechanical and chemical properties. In this review, we focus on the uses of these electroconductive materials in the context of the central and peripheral nervous system, specifically recent studies in the peripheral nerve, spinal cord, brain, eye, and ear. We also highlight in vivo studies and clinical trials, as well as a snapshot of emerging classes of electroconductive materials (e.g., biodegradable materials). We believe such specialized electrically conductive biomaterials will clinically impact the field of tissue regeneration in the foreseeable future.
This review addresses the use of conductive and electroactive materials for neural tissue regeneration, which is of significant interest to a broad readership, and of particular relevance to the growing community of scientists, engineers and clinicians in academia and industry who develop novel medical devices for tissue engineering and regenerative medicine. The review covers the materials that may be employed (primarily focusing on derivatives of fullerenes, graphene and conjugated polymers) and techniques used to analyze materials composed thereof, followed by sections on the application of these materials to nervous tissues (i.e., peripheral nerve, spinal cord, brain, optical, and auditory tissues) throughout the body.
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Bone tissue engineering involves the combined use of materials with functional properties to regenerate bone. Nanohydroxyapatite (nHA) can influence the behavior of cells. The functional and ...structural properties of nHA can be controlled during nanoparticle synthesis. This review defines the relationship between the attributes of nHA nanoparticles and their biological effects, focusing on biocompatibility, surface-area-to-volume ratio, bonding chemistry, and substrate functionality. The paper explores how these aspects have been applied in the development of scaffolds for the repair of damaged bone or regeneration of missing bone.
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