Showing papers in "Nano Reviews in 2017"
TL;DR: The principles and main functions of MNPs in different classes of biosensors according to the transduction methods employed are outlined and the effects of structure, shape, and other physical properties of noble MNPs and nanohybrids in biosensor performance are discussed.
Abstract: The aim of this review is to cover advances in noble metal nanoparticle (MNP)-based biosensors and to outline the principles and main functions of MNPs in different classes of biosensors according to the transduction methods employed. The important biorecognition elements are enzymes, antibodies, aptamers, DNA sequences, and whole cells. The main readouts are electrochemical (amperometric and voltametric), optical (surface plasmon resonance, colorimetric, chemiluminescence, photoelectrochemical, etc.) and piezoelectric. MNPs have received attention for applications in biosensing due to their fascinating properties. These properties include a large surface area that enhances biorecognizers and receptor immobilization, good ability for reaction catalysis and electron transfer, and good biocompatibility. MNPs can be used alone and in combination with other classes of nanostructures. MNP-based sensors can lead to significant signal amplification, higher sensitivity, and great improvements in the detection and quantification of biomolecules and different ions. Some recent examples of biomolecular sensors using MNPs are given, and the effects of structure, shape, and other physical properties of noble MNPs and nanohybrids in biosensor performance are discussed.
199 citations
TL;DR: This review summarizes the current progress in approaches assessing nanotoxicity in main systems, including the hepatic and renal, gastrointestinal, pulmonary, cardiovascular, nervous, and immune systems.
Abstract: Abstract In the past decades, much attention has been paid to toxicity assessment of nanoparticles prior to clinical and biological applications. While in vitro studies have been increasing constantly, in vivo studies of nanoparticles have not established a unified system until now. Predictive models and validated standard methods are imperative. This review summarizes the current progress in approaches assessing nanotoxicity in main systems, including the hepatic and renal, gastrointestinal, pulmonary, cardiovascular, nervous, and immune systems. Histopathological studies and specific functional examinations in each system are elucidated. Related injury mechanisms are also discussed.
157 citations
TL;DR: G gelatin NPs have the ability to cross the blood-brain barrier, hence proven as a promising candidate to target brain disorders, and a wide range of potential applications which needs to be unraveled in more detail are reviewed.
Abstract: Abstract Gelatin is a protein obtained from the hydrolysis of collagen. Gelatin is an attractive biodegradable material for use in nano-biotechnology and nano-pharmaceutics. Gelatin nanoparticles (NPs) have been widely used as drug and gene carrier to targeted sick tissues including cancer, tuberculosis, HIV infection along with the treatment of vasospasm and restenosis, due to its biocompatibility and biodegradability. For instance, coating with gelatin lowers the cytotoxicity of quantum dots. Moreover, gelatin NPs have the ability to cross the blood-brain barrier, hence proven as a promising candidate to target brain disorders. Macrophage targeting with gelatin NPs for remedy of different diseases is repeatedly reported in previous years. In tissue engineering gelatin is actively utilized for construction of biological and life-long 3D scaffolds for bio-artificial tissues and organ production. Gelatins have a wide range of potential applications which needs to be unraveled in more detail. This review is mainly focused on the applications of gelatin NPs in biomedical sciences.
92 citations
TL;DR: The unique challenges presented by the nanoparticle-biocorona are summarized and avenues of future needed investigation are summarized to allow for more effective laboratory screening of nanoparticles and enhanced biomedical applications.
Abstract: Formation of the biocorona on the surface of nanoparticles is a significant obstacle for the development of safe and effective nanotechnologies, especially for nanoparticles with biomedical applications. Following introduction into a biological environment, nanoparticles are rapidly coated with biomolecules resulting in formation of the nanoparticle-biocorona. The addition of these biomolecules alters the nanoparticle's physicochemical characteristics, functionality, biodistribution, and toxicity. To synthesize effective nanotherapeutics and to more fully understand possible toxicity following human exposures, it is necessary to elucidate these interactions between the nanoparticle and the biological media resulting in biocorona formation. A thorough understanding of the mechanisms by which the addition of the biocorona governs nanoparticle-cell interactions is also required. Through elucidating the formation and the biological impact of the biocorona, the field of nanotechnology can reach its full potential. This understanding of the biocorona will ultimately allow for more effective laboratory screening of nanoparticles and enhanced biomedical applications. The importance of the nanoparticle-biocorona has been appreciated for a decade; however, there remain numerous future directions for research which are necessary for study. This perspectives article will summarize the unique challenges presented by the nanoparticle-biocorona and avenues of future needed investigation.
65 citations
TL;DR: This review focuses on recent research on the creation, characterization, and evaluation of NPs for the prevention or treatment of biofilm infections.
Abstract: Abstract Chronic infections have posed a tremendous burden on health care systems worldwide. Approximately 60% of chronic infections are estimated to be related to biofilms, in large part due to the extraordinary antibiotic resistance of biofilm bacteria. Nanoparticle (NP)-based therapies are viable approaches to treat biofilm-associated infections due to NPs’ unique chemical and physical properties, granted by their high surface area to volume ratio. The mechanism underlying the anti-biofilm activity of various types of NPs is actively under investigation. Simply comparing biofilm disruption or reduction rates is not adequate to describe the effectiveness of NPs; many other factors need to be taken into account, such as the NP type, bacterial strain, concentration of NPs, quantification methods, and the biofilm culture environment. This review focuses on recent research on the creation, characterization, and evaluation of NPs for the prevention or treatment of biofilm infections.
54 citations
TL;DR: A major goal of this review is to summarize the achievements that have been made in the development of the application of nanomaterials for cancer therapies, along with a short description of their general characteristics and preparation of various kinds of nanoparticles.
Abstract: Abstract Cancer is one of the most deadly diseases in the world. In recent years, nanotechnology, as a unique technology, has been comprehensively applied in the therapy of cancer through diagnosis, imaging and theranostics. Additionally, with the emergence of advanced biomaterials which are capable of being applied in biomedical, research in cancer nanotechnology has made significant progress. Particularly, nanomaterials with dimensions below several hundred nanometers are intensively studied among these advanced biomaterials. In past decades, a number of organic and inorganic nanomaterials have emerged as novel tools for cancer diagnostics and therapeutics due to their unique characteristics, like their solubilization effect, drug protection, passive/active tumor targeting, controlled release of drugs which result in enhanced anticancer efficacy while reducing the side effects. In this review, we first provide a brief description of the key properties of nanomaterials, such as nanoparticle (NP) size, surface properties and tumor targeting. The major goal of this review is to summarize the achievements that have been made in the development of the application of nanomaterials for cancer therapies, along with a short description of their general characteristics and preparation of various kinds of nanoparticles.
51 citations
TL;DR: This paper presents an on-column method for nanodisc preparation with multiple strategies and discusses the potential use of alternative nanoscale phospholipid bilayer systems like styrene maleic acid lipid disc and saposin-A lipoprotein disc.
Abstract: Nanodiscs provide an excellent system for the structure-function investigation of membrane proteins. Its direct advantage lies in presenting a water soluble form of an otherwise hydrophobic molecule, making it amenable to a plethora of solution techniques. Nuclear Magnetic Resonance is one such high resolution approach that looks at the structure and dynamics of a protein with atomic level precision. Recently, there has been a breakthrough in making nanodiscs more susceptible for structure determination by solution NMR, yet it still remains to become the preferred choice for a membrane mimetic. In this practical review, we provide a general discourse on nanodisc and its application to solution NMR. We also offer potential solutions to remediate the technical challenges associated with nanodisc preparation and the choice of proper experimental set-ups. Along with discussing several structural applications, we demonstrate an alternative use of nanodiscs for functional studies, where we investigated the phosphorylation of a cell surface receptor, Integrin. This is the first successful manifestation of observing activated receptor phosphorylation in nanodiscs through NMR. We additionally present an on-column method for nanodisc preparation with multiple strategies and discuss the potential use of alternative nanoscale phospholipid bilayer systems like SMA lipid discs and Saposin-A lipoprotein discs.
43 citations
TL;DR: In this paper, deep eutectic solvents (DESs) were used for various purposes based on their unique chemical and physical properties for the synthesis of noble metal nanomaterials.
Abstract: Abstract Deep eutectic solvents (DESs) were developed 15 years ago and have been used for various purposes based on their unique chemical and physical properties. Recently, they have been highlighted as versatile media for the synthesis of noble metal nanomaterials. Although there are a few limitations, their vast chemical library of hydrogen bond donors and excellent solubility show great potential for their future applications for the synthesis of noble metal nanoparticles.
37 citations
TL;DR: In this paper, a review of magnetically recoverable nano-catalysts for sulfoxidation reactions is presented, focusing on metal complexes, acid, and bromine reagents supported on magnetic nanoparticles.
Abstract: Abstract The sulfoxidation of sulfides have received special attention in organic synthesis especially in medical chemistry because compounds containing S=O bonds (sulfoxides) are privileged structural scaffolds for building pharmacologically and biologically active molecules. Magnetic separation is an efficient strategy for the rapid separation of catalysts from reaction medium and an alternative to time-, solvent-, and energy-consuming separation techniques. In recent times, many protocols based on using magnetically recoverable nano-catalysts have been reported for the oxidation of sulfides to the sulfoxides. This review is focused on metal complexes, acid, and bromine reagents supported on magnetic nanoparticles and their applications as magnetically recoverable nano-catalysts in the sulfoxidation reactions.
34 citations
TL;DR: A critical review of the literature information on nanostructured biomaterials for enzyme delivery is shown and it is shown that they are biocompatible and biodegradable materials.
Abstract: Abstract Application of nanotechnology is making huge progress in the biomedical and environmental fields. The design and production of nanoreactors based on the combination of catalytic properties of enzymes and the unique characteristics of nano-sized materials is, certainly, an opportunity to solve different challenges in biomedical and environmental fields. Most of the research efforts to combine enzymes and nanostructured materials have been made using ceramic, metallic, or carbon-based materials. Nevertheless, biomaterials, or materials from biological origin, have two main advantages for biomedical and environmental applications when compared with non-biological nanomaterials; they are biocompatible and biodegradable materials. In this work, a critical review of the literature information on nanostructured biomaterials for enzyme delivery is shown.
32 citations
TL;DR: In this paper, a review of the chemical strategies used for the modification of the inner surface of halloysite nanotubes (HNTs) is presented, which is usually intended to decrease the HNT dispersal in aqueous media.
Abstract: Abstract In this paper, we review the chemical strategies used for the modification of the inner surface of halloysite nanotubes (HNTs). The HNTs are nanotubular materials formed by rolling up the 1:1 aluminosilicate clays, where the composition is similar with kaolin. Owing to many virtues, including the high ratio of length to diameter, large cavity volume, desirable biocompatibility, and low cost, the HNTs have been applied to numerous promising domains. The modification of the outer surface is usually intended to decrease the HNT dispersal in aqueous media. Considering that the selective modification for the inner surface gives excellent prospects for hybrid HNT-based materials, herein, we explore the advances in the selective modification of the inner surface that expanded the applications of the HNTs.
TL;DR: In this article, the potential emission of nanocomponents into the environment can be considered and should be considered, as well as some problems related to the potential emissions of nanocomposite-based components.
Abstract: Abstract Nanotechnology allows for the development of new types of materials containing antimicrobial properties. Nanocomposite-based products are increasingly applied in medicine, industry and everyday life. Antibacterial features allow the use of nanoproducts in filters for water and air purification, textiles, food packages, medical materials and devices, ceramics, glass, plastics, paints, cosmetics and personal care products. Numerous studies concern the synthesis of novel antimicrobial nanoproducts as well as modification of already existing nanomaterials in order to supply them with antibacterial activity. However, some problems related to the potential emission of nanocomponents into the environment can appear and should be considered.
TL;DR: In this article, a co-precipitation technique was used to obtain a phase-pure, highly crystalline HA nanorods using X-ray photo-electron spectroscopy (XPS).
Abstract: Abstract Synthetic nanosized hydroxyapatite (HA) particles (<120 nm) were prepared using a co-precipitation technique by adopting two different routes – one from an aqueous solution of calcium nitrate tetrahydrate and diammonium hydrogen phosphate at pH 10 and the other by using calcium hydroxide and phosphoric acid as precursors at pH 8.5 and reaction temperature of 50°C. The lattice parameters of HA nanopowder were analogous to reference [Joint Committee on Powdered Diffraction Standards (JCPDS)] pattern no. 09-432. No decomposition of HA into other phases was observed even after heating at 1000°C in air for 1 h. This observation revealed the high-temperature stability of the HA nanopowder obtained using co-precipitation route. The effects of preliminary Ca/P molar ratio, precipitation, pH and temperature on the evolution of phase and crystallinity of the nanopowder were systematically examined and optimized. The product was evaluated by techniques such as X-ray-diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared (FTIR) and Raman spectroscopy analyses. The chemical structural analysis of the as-prepared HA sample was performed using X-ray photoelectron spectroscopy (XPS). After heat treatment at 1000°C for 1 h and ageing for 15 h, the product was obtained as a phase-pure, highly crystalline HA nanorods.
TL;DR: The recent advances in the field of membrane mimetics for solution NMR studies are reviewed, the advantages and drawbacks of specific membrane-like environments are discussed, and the criteria for the selection of proper environment for a particular membrane protein or domain is formulated.
Abstract: Abstract Membrane proteins are one of the most challenging and attractive objects in modern structural biology, as they are targets for the majority of medicines. However, studies of membrane proteins are hindered by several obstacles, including their low ability to crystallize, highly dynamic behavior of some of their domains, and need for membrane-like environment. Although solution nuclear magnetic resonance (NMR) is a very powerful technique of structural biology in terms of the amount of provided data, it imposes several limitations on the object under investigation, with the main constraint being related to the size of the object. For this reason, the membrane mimetic has to form particles of small size and simultaneously to properly simulate the bilayer membrane to be applicable for solution NMR spectroscopy. Here we review the recent advances in the field of membrane mimetics for solution NMR studies, discuss the advantages and drawbacks of specific membrane-like environments, and formulate the criteria for the selection of proper environment for a particular membrane protein or domain.
TL;DR: Compared with systematic administration such as peripheral intravenous infusion, stem cell therapy by direct injection is theoretically more effective, but some technical barriers such as low stem cell retention rate and low engraftment rate still need to be overcome before its application in humans.
Abstract: Abstract Compared with systematic administration such as peripheral intravenous infusion, stem cell therapy by direct injection is theoretically more effective, but some technical barriers such as low stem cell retention rate and low engraftment rate still need to be overcome before its application in humans. Stem cell therapy supported by hydrogel carriers has been increasingly studied in recent years. These hydrogels with properties similar to natural tissues are able to fabricate various forms of carriers, which include in situ forming hydrogels, ex situ forming hydrogels, surface immobilization carriers, microencapsules, and microgels. Some of them are 3D carriers and promise to overcome the technical barriers of stem cell therapy by direct injection. They have different characteristics, application, and prospect in the application of stem cell therapy by direct injection, which is summarized by this review.
TL;DR: A detailed summary of state-of-the-art coating strategies in ALD, emphasizing the recent progress in the fabrication of novel nanostructures, is provided in this article, in which the progress in coating strategies is reviewed in three parts: template-assisted preparation of low-dimensional nanomaterials and complex structures; surface treatments, including the surface activation and the surface blocking ways; enhanced reactor, such as plasma and fluid bed reactor, and improved growth method such as ABC-type model.
Abstract: Abstract Atomic layer deposition (ALD) is a vapor phase technique capable of producing a variety of materials. It consists of the alternation of separate self-limiting surface reactions, which enables accurate control of film thickness at the Angstrom level. ALD becomes a powerful tool for a lot of industrial and research applications. Coating strategies are the key for ALD; however, there are few systematic reviews concerning coating strategies for ALD. This review provides a detailed summary of state-of-the-art coating strategies in ALD, emphasizing the recent progress in the fabrication of novel nanostructures. The progress in coating strategies is reviewed in three parts: template-assisted preparation of low-dimensional nanomaterials and complex nanostructures; surface treatments, including the surface activation and the surface blocking ways; enhanced reactor, such as plasma and fluid bed reactor, and improved growth method such as the ABC-type model. In addition, we also discussed the challenges facing the coating method for ALD.
TL;DR: The photoluminescence (PL) properties of Si NPs have been extensively studied in the literature as mentioned in this paper, with a focus on the properties of surface chemistry, such as surface nitrogen capping and surface oxidation.
Abstract: Abstract Silicon nanoparticles (NPs) have long been regarded as a promising alternative for commercial organic dyes and typical quantum dots (e.g. CdSe) for applications in light emitting, bio-imaging, sensing, etc. The photoluminescence (PL) of Si NPs, since the first observation in the early 1990s, now has shown wide tunability in the PL wavelength ranging from UV to near IR and lifetime from less than nanoseconds to hundreds of microseconds. Meanwhile, the synthetic advances and methods of size separation and surface modification have improved the quantum yield of Si NPs up to 90% and the PL bandwidth down to ~30 nm FWHM. On the other hand, despite more than 20 years of research, it remains controversial in terms of the exact origin and mechanism of the PL from Si NPs. In this review, we intend to relate the structure of Si NPs with their optical properties in the hope of revealing some general, underlying laws of the size/surface-property relationships based on the reported research. Especially, we highlight the latest research progress on the complex influences of surface chemistry, such as the surface nitrogen capping and surface oxidation, which can dramatically alter and enhance the PL properties of Si NPs.
TL;DR: Important advanced characterization techniques of nanoformulation with respect to their theories, use of required instrumental parameters, sample preparation techniques, data interpretation, etc., are summarized to exploit them for the best possible results.
Abstract: Nanomedicine has achieved a huge success in delivering a wide variety of drug molecules into the target site of the body. In this respect characterization of nano formulation is very important to investigate the drug molecule together with its carrier as a nano form during formulation, storage and in vivo transport through the body. This review article summarizes important advanced characterization techniques of nano formulation with respect to their theories, the use of required instrumental parameters, sample preparation techniques, data interpretation, etc. in order to exploit them for the best possible results. This review article
also sheds a glimpse to the shortcomings of these techniques together with further advancements required in future.
TL;DR: In this article, the role of a proper determination of the surface area of 2D materials, considering the presence of defects, in determining the capacitance and the magnitude of the energy storage is also considered.
Abstract: Abstract The inevitable presence of defects in graphene and other two-dimensional (2D) materials influences the charge density and distribution along with the concomitant measured capacitance and the related energy density. We review, in this paper, the various manifestations of the capacitance including both the classical electrostatic (e.g. associated with double layer, space charge, chemical capacitances) and the quantum forms, as well as a few methodologies to tune the respective capacitances. The role of a proper determination of the surface area of 2D materials, considering the presence of defects, in determining the capacitance and the magnitude of the energy storage is also considered.
TL;DR: All PLGA nanoparticles studied, independent of the synthesis method and size, adhered to the surface of RBCs but had no significant hemolytic effect at concentrations lower than 10 mg/ml.
Abstract: Abstract With the increasing interest in polymeric nanoparticles for biomedical applications, there is a need for continuous flow methodologies that allow for the precise control of nanoparticle synthesis. Poly(lactide-co-glycolic) acid (PLGA) nanoparticles with diameters of 220–250 nm were synthesized using a lab-on-a-chip, exploiting the precise flow control offered by a millifluidic platform. The association and the effect of PLGA nanoparticles on red blood cells (RBCs) were compared for fluorescent PLGA nanoparticles made by this novel continuous flow process using a millifluidic chip and smaller PLGA nanoparticles made by a batch method. Results indicated that all PLGA nanoparticles studied, independent of the synthesis method and size, adhered to the surface of RBCs but had no significant hemolytic effect at concentrations lower than 10 mg/ml.
TL;DR: The study shows the highlights and importance of magnetic targeting to optimize the magnetic targeting process as a therapeutic strategy for gliomas, an innovative nanobiotechnological method.
Abstract: Abstract The purpose of this study was to review the use of the magnetic targeting technique, characterized by magnetic driving compounds based on superparamagnetic iron oxide nanoparticles (SPIONs), as drug delivery for a specific brain locus in gliomas. We reviewed a process mediated by the application of an external static magnetic field for targeting SPIONs in gliomas. A search of PubMed, Cochrane Library, Scopus, and Web of Science databases identified 228 studies, 23 of which were selected based on inclusion criteria and predetermined exclusion criteria. The articles were analyzed by physicochemical characteristics of SPIONs used, cell types used for tumor induction, characteristics of experimental glioma models, magnetic targeting technical parameters, and analysis method of process efficiency. The study shows the highlights and importance of magnetic targeting to optimize the magnetic targeting process as a therapeutic strategy for gliomas. Regardless of the intensity of the patterned magnetic field, the time of application of the field, and nanoparticle used (commercial or synthesized), all studies showed a vast advantage in the use of magnetic targeting, either alone or in combination with other techniques, for optimized glioma therapy. Therefore, this review elucidates the preclinical and therapeutic applications of magnetic targeting in glioma, an innovative nanobiotechnological method.
TL;DR: In this paper, the reduced graphene oxide-Bi2WO6 (rGO-BWO) photocatalysts with different RM values (mass ratio of GO and Bi 2 WO6) were successfully synthesized via hydrothermal method in the presence of GO.
Abstract: Abstract The reduced graphene oxide-Bi2WO6 (rGO-BWO) photocatalysts with different RM values (mass ratio of GO and Bi2WO6) had been successfully synthesized via hydrothermal method in the presence of GO. When increasing the RM values from 0 to 2%, the evident red shift of the absorption edges of rGO-BWO samples occurred, and the photocatalytic activities for the degradation of Rhodamine-B were enhanced gradually. However, there was a significant blue shift in the absorbance band, and the morphology of the incomplete rGO-BWO microspheres led to the lower photocatalytic activity when RM is increased from 4 to 10%. The enhanced photocatalytic activity can be attributed to the smaller band gap, which means needing less energy for the electron transition, the morphology of the unbroken microsphere that provides more possible reaction sites for the photocatalytic reaction, the appropriate GO content that may effectively mitigate electron-hole pair recombination by the migration of photoinduced electrons.
TL;DR: This review focuses on electron paramagnetic resonance with site-directed nitroxide spin-labeling (SDSL EPR), which is a rapidly expanding and powerful technique reporting on the local protein/spin-label dynamics and on large functionally important structural rearrangements.
Abstract: Abstract Cellular membranes and associated proteins play critical physiological roles in organisms from all life kingdoms. In many cases, malfunction of biological membranes triggered by changes in the lipid bilayer properties or membrane protein functional abnormalities lead to severe diseases. To understand in detail the processes that govern the life of cells and to control diseases, one of the major tasks in biological sciences is to learn how the membrane proteins function. To do so, a variety of biochemical and biophysical approaches have been used in molecular studies of membrane protein structure and function on the nanoscale. This review focuses on electron paramagnetic resonance with site-directed nitroxide spin-labeling (SDSL EPR), which is a rapidly expanding and powerful technique reporting on the local protein/spin-label dynamics and on large functionally important structural rearrangements. On the other hand, adequate to nanoscale study membrane mimetics have been developed and used in conjunction with SDSL EPR. Primarily, these mimetics include various liposomes, bicelles, and nanodiscs. This review provides a basic description of the EPR methods, continuous-wave and pulse, applied to spin-labeled proteins, and highlights several representative applications of EPR to liposome-, bicelle-, or nanodisc-reconstituted membrane proteins.
TL;DR: In this article, the authors examined the current regulation of nanotechnology and its medical applications in Australia, and observed that it would be premature to impose any stringent regulation at this stage on medical experimentations.
Abstract: Nanobiotechnology is an immensely potential invention, which is expected to bring about revolutionary changes in many aspects of essential human needs including medical treatments and foods. Although the technology has passed through its embryonic stage, its medical applications in preparing and delivering drugs to target cells of human bodies to cure incurable diseases are still under scientific scrutiny. A 2007 study suggests that Australia needs to have a review of its regulatory framework for nanotechnology by 2017. This article examines the current regulation of nanotechnology and its medical applications in Australia, and observes that it would be premature to impose any stringent regulation at this stage on medical experimentations. We are of the view that an excessively precautionary policy may hinder further research, which is critical to discovering the benefit and harm with certainty. Hence, in the greater interest of the facilitation of research and affirmation of benefits of this technology, we recommend that adopting a hybrid regulatory method composed of self-regulation and accommodating government regulation would be an appropriate policy approach to the regulation of nanobiotechnology. We also accept the need for a set of internationally harmonized policy principles to guide our actions in relation to this technology.
TL;DR: The formation of ordered arrays akin to weakly ordered two-dimensional crystals in the bilayer of liposomes as a means to achieve high-resolution, and subsequent buffer modification as a method to capture snapshots of membrane proteins in action are suggested.
Abstract: Abstract Membrane proteins are vital to life and major therapeutic targets. Yet, understanding how they function is limited by a lack of structural information. In biological cells, membrane proteins reside in lipidic membranes and typically experience different buffer conditions on both sides of the membrane or even electric potentials and transmembrane gradients across the membranes. Proteoliposomes, which are lipidic vesicles filled with reconstituted membrane proteins, provide an ideal model system for structural and functional studies of membrane proteins under conditions that mimic nature to a certain degree. We discuss methods for the formation of liposomes and proteoliposomes, their imaging by cryo-electron microscopy, and the structural analysis of proteins present in their bilayer. We suggest the formation of ordered arrays akin to weakly ordered two-dimensional (2D) crystals in the bilayer of liposomes as a means to achieve high-resolution, and subsequent buffer modification as a method to capture snapshots of membrane proteins in action.
TL;DR: A top-level description of the policy, infrastructure, and human capital development programs supported by the South African government and the nanomedicine outputs that have emanated from South Africa are provided.
Abstract: Abstract Nanomedicine is one of the most exciting applications of nanotechnology and promises to address several of mankind’s healthcare needs. South Africa is one of the countries engaged in nanomedicine research and product development on the African continent. In this article, we provide a top-level description of the policy, infrastructure, and human capital development programs supported by the South African government. We also highlight the nanomedicine outputs (publications, patents, and products) that have emanated from South Africa. This description of a “newly industrialized” country engagement in nanomedicine is important within the global context of nanomedicine development.
TL;DR: An overview of the status of pre-clinical mice models for types 1 and 2 diabetic wound healing and relate this to studies conducted with polymeric nanoscaffolds is given.
Abstract: Abstract Tissue-engineered scaffolds for skin wound healing have undergone tremendous progress since the advent of autologous skin grafts or autografts. The recognition that a three-dimensional (3D) scaffold more closely mimics the biochemical-mechanical milieu of wounds and advancing knowledge of cell biology has led to the next-generation of engineered biopolymeric nanoscaffolds. These can pave the way towards personalized wound care as they can address multiple requirements of skin physiology. A unifying approach is required for translational success of scaffolds, involving clinicians, biologists, and chemists. Following in vitro testing using cell lines, pre-clinical studies on animal models is the next crucial step towards scaffold clinical translation. Often, success noted in these studies does not replicate in human patients due to the heterogeneous nature of wound conditions and causes that cannot be found in a single animal model. In this review, we give an overview of the status of pre-clinical mice models for types 1 and 2 diabetic wound healing and relate this to studies conducted with polymeric nanoscaffolds. Translational shortcomings of these models are analyzed where they fail to provide a good replica of human conditions. Categorization and use of more sophisticated models, which can closely mimic the diabetic features, are addressed for translational use of nanoscaffolds.
TL;DR: This review discusses the documented achievements and concerns associated with broad potential applications of nanoforms in the fight against microorganisms and indicates that modern nanoforms can effectively support and perhaps in the long-term replace traditional bactericidal agents.
Abstract: Abstract Antimicrobial resistance is still a crucial global problem related to the overuse of antibiotics and natural microorganism capability for rapid horizontal evolution. Even new generations of drugs are not able to overcome bacterial defence mechanisms. A novel solution for this immense medical challenge can be nanomaterials. Researchers indicate that modern nanoforms can effectively support and perhaps in the long-term replace traditional bactericidal agents. Because of their unique physicochemical properties, nanotechnology products can exert multiple actions against bacteria, which might be efficient against even multidrug-resistant pathogens. In this review, we discuss the documented achievements and concerns associated with broad potential applications of nanoforms in the fight against microorganisms.
TL;DR: In this article, the importance of the III-V semiconductor nanostructured channel in MOSFETs was highlighted with a proposed III-v GaN-based channel (thickness of 10 nm); Al2O3 dielectric gate oxide based MOS-FET is reported with a very low threshold voltage of 0.1 V and faster switching of the device.
Abstract: Abstract The quest for high device density in advanced technology nodes makes strain engineering increasingly difficult in the last few decades. The mechanical strain and performance gain has also started to diminish due to aggressive transistor pitch scaling. In order to continue Moore’s law of scaling, it is necessary to find an effective way to enhance carrier transport in scaled dimensions. In this regard, the use of alternative nanomaterials that have superior transport properties for metal-oxide-semiconductor field-effect transistor (MOSFET) channel would be advantageous. Because of the extraordinary electron transport properties of certain III–V compound semiconductors, III–Vs are considered a promising candidate as a channel material for future channel metal-oxide-semiconductor transistors and complementary metal-oxide-semiconductor devices. In this review, the importance of the III–V semiconductor nanostructured channel in MOSFET is highlighted with a proposed III–V GaN nanostructured channel (thickness of 10 nm); Al2O3 dielectric gate oxide based MOSFET is reported with a very low threshold voltage of 0.1 V and faster switching of the device.