细菌纤维素纳米复合物的研究进展

细菌纤维素是一种新型的生物材料,具有很多优良的性能,在伤口敷料、人造血管、人工皮肤及组织工程领域有着广阔的应用前景.近年来,国外研究者采用纳米复合技术对细菌纤维素进行了修饰,以赋予细菌纤维素新的性能.综合介绍了目前国外关于细菌纤维素纳米复合物的研究进展及其应用情况.     

Emerging Porous Two-Dimensional Materials: Current Status,Existing Challenges,and Applications

Two-Dimensional (2D) materials have attracted immense attention in recent years. These materials have found their applications in various fields, such as catalysis, adsorption, energy storage, and sensing, as they exhibit excellent physical, chemical, electronic, photonic, and biological properties. Recently, researchers have focused on constructing porous structures on 2D materials. Various strategies, such as chemical etching and template-based methods, for the development of surface pores are reported, and the porous 2D materials fabricated over the years are used to develop supercapacitors and energy storage devices. Moreover, the lattice structure of the 2D materials can be modulated during the construction of porous structures to develop 2D materials that can be used in various fields such as lattice defects in 2D nanomaterials for enhancing biomedical performances. This review focuses on the recently developed chemical etching, solvent thermal synthesis, microwave combustion, and template methods that are used to fabricate porous 2D materials. The application prospects of the porous 2D materials are summarized. Finally, the key scientific challenges associated with developing porous 2D materials are presented to provide a platform for developing porous 2D materials.     

Advances in Biomimetic and Nanostructured Biohybrid Materials

The rapid increase of interest in the field of biohybrid and biomimetic materials that exhibit improved structural and functional properties is attracting more and more researchers from life science, materials science, and nanoscience. Concomitant results offer valuable opportunities for applications that involve disciplines dealing with engineering, biotechnology, medicine and pharmacy, agriculture, nanotechnology, and others. In the current contribution we collect recent illustrative examples of assemblies between materials of biological origin and inorganic solids of different characteristics (texture, structure, and particle size). We introduce here a general overview on strategies for the preparation and conformation of biohybrids, the synergistic effects that determine the final properties of these materials, and their diverse applications, which cover areas as different as tissue engineering, drug delivery systems, biosensing devices, biocatalysis, green nanocomposites, etc.     

Synthesis and application of quantum dot-tagged fluorescent microbeads

Fluorescent quantum dots have been used in biological applications as desirable fluorescent labels instead of traditional fluorophores. Incorporation into microspheres enhances many features of quantum dots that make them ideal for biological detection, such as photostability, multi-target, and improved brightness. Quantum dot-tagged microbeads are emerging as a new class of fluorescent labels and are expected to open new opportunities in nanotechnology and biology. In this review, we describe different approaches for the synthesis of quantum dot-tagged microbeads, surface modification methods that make microbeads suitable for bioconjugation, and the biological applications of the quantum dot-tagged fluorescent microbeads with their desired features in recent research. We also discuss the limitations of some kinds of quantum dot-tagged microbeads and the developments that will enhance their abilities in biological applications.     

Chemistry of Mesoporous Organosilica in Nanotechnology: Molecularly Organic–Inorganic Hybridization into Frameworks

Organic–inorganic hybrid materials aiming to combine the individual advantages of organic and inorganic components while overcoming their intrinsic drawbacks have shown great potential for future applications in broad fields. In particular, the integration of functional organic fragments into the framework of mesoporous silica to fabricate mesoporous organosilica materials has attracted great attention in the scientific community for decades. The development of such mesoporous organosilica materials has shifted from bulk materials to nanosized mesoporous organosilica nanoparticles (designated as MONs, in comparison with traditional mesoporous silica nanoparticles (MSNs)) and corresponding applications in nanoscience and nanotechnology. In this comprehensive review, the state‐of‐art progress of this important hybrid nanomaterial family is summarized, focusing on the structure/composition–performance relationship of MONs of well‐defined morphology, nanostructure, and nanoparticulate dimension. The synthetic strategies and the corresponding mechanisms for the design and construction of MONs with varied morphologies, compositions, nanostructures, and functionalities are overviewed initially. Then, the following part specifically concentrates on their broad spectrum of applications in nanotechnology, mainly in nanomedicine, nanocatalysis, and nanofabrication. Finally, some critical issues, presenting challenges and the future development of MONs regarding the rational synthesis and applications in nanotechnology are summarized and discussed. It is highly expected that such a unique molecularly organic–inorganic nanohybrid family will find practical applications in nanotechnology, and promote the advances of this discipline regarding hybrid chemistry and materials.     

Selenium nanomaterials: An overview of recent developments in synthesis,properties and potential applications

Advances in science and nanotechnology have facilitated the development of new methods for the preparation of pure selenium as selenium nanomaterials. They offer remarkable potential for technological applications in the fields of medicine, diagnostics, therapeutics, toxicology, electronics, catalysis and so on. Moreover, selenium nanomaterials also find applications in photographic exposure metres, rectifiers, signal emitting devices and transmitting devices, because of their unique structural, optical and electronic properties. This study describes a detailed advanced report on the synthesis, assembly, characterization and various applications of selenium nanomaterials. In addition, relevant synthesis methods, properties, challenges and opportunities associated with selenium nanomaterials are also presented.     

Nanostructured bioceramics for maxillofacial applications

Biomaterials science and technology have been expanding tremendously the recent years. The results of this evolution are obvious in maxillofacial applications especially with the contemporary development of Nanotechnology. Among biomaterials, bioceramics possess a specific field due to various interactions with the biological tissues. The combination of bioceramics and nanotechnology has resulted in enhanced skeletal interactions in maxillofacial applications. Nanotechnology secures better mechanical properties and more effective biological interactions with jaws. The main production methods for the synthesis of nanostructured materials include plasma arcing, chemical vapour deposition, sol–gel and precipitation. The bioceramics in Dentistry comprise inert, bioactive, resorbable and composite systems. The purpose of the present article is to describe the available nanotechnology methods and how these could be addressed to synthesise maxillofacial bioceramics with advanced properties for better biological applications. Additionally, it describes specific clinical applications in maxillofacial surgery of these biomaterials—either by themselves or in combination with others—that can be promising candidates for bone tissue engineering. Such applications include replacement of lost teeth, filling of jaws defects or reconstruction of mandible and temporomandibular joint.     

有序介孔材料的合成及机理

有序介孔材料作为一种新型的纳米结构材料，近年来已成为跨学科的国际研究热点之一。综述了有序介孔材料的合成及其机理，指出有序介孔材料在分离、催化、纳米技术等领域的潜在应用价值。     

Nanocrystalline calcium phosphate ceramics in biomedical engineering

Nanocrystalline calcium phosphate based bioceramics are the new rage in biomaterials research. Conventionally, calcium phosphates based materials are preferred as bone grafts in hard tissue engineering because of their superior biocompatibility and bioactivity. However, this group of bioceramics exhibits poor mechanical performance, which restricts their uses in load bearing applications. The recent trend in bioceramic research is mainly concentrated on bioactive and bioresorbable ceramics, i.e. hydroxyapatite, bioactive glasses, tricalcium phosphates and biphasic calcium phosphates as they exhibit superior biological properties over other materials. In recent times, the arena of nanotechnology has been extensively studied by various researchers to overcome the existing limitations of calcium phosphates, mainly hydroxyapatite, as well as to fabricate nanostructured scaffolds to mimic structural and dimensional details of natural bone. The bone mineral consists of tiny HAp crystals in the nano-regime. It is found that nanocrystalline HAp powders improve sinterability and densification due to greater surface area, which could improve the fracture toughness and other mechanical properties. Nano-HAp is also expected to have better bioactivity than coarser crystals. Nanocrystalline calcium phosphate has the potential to revolutionize the field of hard tissue engineering from bone repair and augmentation to controlled drug delivery devices. This paper reviews the current state of knowledge and recent developments of various nanocrystalline calcium phosphate based bioceramics from synthesis to characterization.     

Recent progress on magnetic iron oxide nanoparticles: synthesis,surface functional strategies and biomedical applications

This review focuses on the recent development and various strategies in the preparation, microstructure, and magnetic properties of bare and surface functionalized iron oxide nanoparticles (IONPs); their corresponding biological application was also discussed. In order to implement the practical in vivo or in vitro applications, the IONPs must have combined properties of high magnetic saturation, stability, biocompatibility, and interactive functions at the surface. Moreover, the surface of IONPs could be modified by organic materials or inorganic materials, such as polymers, biomolecules, silica, metals, etc. The new functionalized strategies, problems and major challenges, along with the current directions for the synthesis, surface functionalization and bioapplication of IONPs, are considered. Finally, some future trends and the prospects in these research areas are also discussed.     

Synthesis and characterization of large specific surface area nanostructured amorphous silica materials

Large specific surface area materials attract wide attention because of their applications in adsorption, catalysis, and nanotechnology. In the present study, we describe the synthesis and characterization of nanostructured amorphous silica materials. These materials were obtained by means of a modification of the Stobe-Fink-Bohn (SFB) method. The morphology and essential features of the synthesized materials have been studied using an automated surface area and pore size analyzer and scanning electron microscopy. The existence of a micro/mesoporous structure in the obtained materials has been established. It was also found that the obtained particle packing materials show large specific surface area up to 1,600 m2/g. (To our best knowledge, there is no any reported amorphous silica material with such a higher specific surface area.) The obtained materials could be useful in the manufacture of adsorbents, catalyst supports, and other nanotechnological applications.     

Carbon Dots‐in‐Matrix Boosting Intriguing Luminescence Properties and Applications

As a new class of luminescent nanomaterials, carbon dots (CDs) have aroused significant interest because of their fascinating photoluminescence properties and potential applications in biological, optoelectronic, and energy‐related fields. Strikingly, embedding CDs in host matrices endow them with intriguing luminescent properties, in particular, room temperature phosphorescence and thermally activated delayed fluorescence, due to the confinement effect of the host matrix and the H‐bonding interactions between CDs and the matrix. Here, the state‐of‐the‐art strategies for introducing CDs in various host matrices are summarized, such as nanoporous materials, polyvinyl alcohol, polyurethane, potash alum, layered double hydroxides, amorphous silica, etc. The resultant luminescent properties of the composites and their emission mechanisms are discussed. Their applications in bioimaging, drug delivery/release, sensing, and anticounterfeiting are also presented. Finally, current problems and challenges of CDs‐based composites are noted for future development of such luminescent materials.     

Controllable synthesis and biomedical applications of silver nanomaterials

Silver nanomaterials have lots of peculiar and exciting physical and chemical properties that are different from massive silver, so the synthesis and applications of silver nanomaterials have attracted a great deal of attention in the last decade. Currently, all kinds of silver nanomaterials having different shapes and sizes have been synthesized by many ingenious methods, and silver nanomaterials have exhibited extensive application prospects in many fields especially in biomedical aspect. In this article, the controllable synthesis of silver nanomaterials including nanorods, nanowires, nanotubes, nanoprisms, nanoplates, nanodisks, nanospheres, and nanopolyhedrons, etc. are reviewed. Silver nanomaterials are most utilized in the form of nanoparticles, so the main biomedical applications of silver nanoparticles, such as antibacterial and antiviral applications, antitumor applications, biosensors and biological labels, optical imaging and imaging intensifier, are discussed. Although antibacterial applications are still the most important aspects of silver nanomaterials at present, antitumor, optical sensors and imaging applications of silver nanomaterials have also shown good potential perspectives. More biomedical applications of silver nanomaterials still need to be exploited for the future, and the biological safety of silver nanomaterials also should be paid enough attention before their practical applications.     

Polymer/bioactive glass nanocomposites for biomedical applications: A review

Nanoscale bioactive glasses have been gaining attention due to their reported superior osteoconductivity when compared to conventional (micron-sized) bioactive glass materials. The combination of bioactive glass nanoparticles or nanofibers with polymeric systems enables the production of nanocomposites with potential to be used in a series of orthopedic applications, including scaffolds for tissue engineering and regenerative medicine. This review presents the state of art of the preparation of nanoscale bioactive glasses and corresponding composites with biocompatible polymers. The recent developments in the preparation methods of nano-sized bioactive glasses are reviewed, covering sol–gel routes, microemulsion techniques, gas phase synthesis method (flame spray synthesis), laser spinning, and electro-spinning. Then, examples of the preparation and properties of nanocomposites based on such inorganic bionanomaterials are presented, obtained using various polymer matrices, including polyesters such as poly(hydroxybutyrate), poly(lactic acid) and poly(caprolactone), and natural-based polymers such as polysaccharides (starch, chitin, chitosan) or proteins (silk fibroin, collagen). The physico-chemical, mechanical, and biological advantages of incorporating nanoscale bioactive glasses in such biodegradable nanocomposites are discussed and the possibilities to expand the use of these materials in other nanotechnology concepts aimed to be used in different biomedical applications are also highlighted.     

Recent progress on magnetic iron oxide nanoparticles: synthesis,surface functional strategies and biomedical applications

Abstract

This review focuses on the recent development and various strategies in the preparation, microstructure, and magnetic properties of bare and surface functionalized iron oxide nanoparticles (IONPs); their corresponding biological application was also discussed. In order to implement the practical in vivo or in vitro applications, the IONPs must have combined properties of high magnetic saturation, stability, biocompatibility, and interactive functions at the surface. Moreover, the surface of IONPs could be modified by organic materials or inorganic materials, such as polymers, biomolecules, silica, metals, etc. The new functionalized strategies, problems and major challenges, along with the current directions for the synthesis, surface functionalization and bioapplication of IONPs, are considered. Finally, some future trends and the prospects in these research areas are also discussed.     

Synthesis of Carbon‐Nanotube Composites Using Supercritical Fluids and Their Potential Applications

Carbon‐nanotube (CNT) composites have attracted a lot of attention because of their potential applications in many fields. Here, recent advances in the synthesis of CNT composites using supercritical fluids (SCFs) are highlighted. SCFs exhibit unique features for the synthesis of composites because of their unusual properties, such as low viscosity, high diffusivity, near‐zero surface tension, and tunability. Preliminary studies show that SCFs show unusual advantages for the synthesis of CNT composites. The morphologies and structures of the resultant CNT composites can be tuned by changing the solvent properties. The SCF methods not only provide a green route for the synthesis of composites, but also result in nanostructures that have not yet been produced by conventional methods. Moreover, the potential applications of the resultant CNT composites are also discussed.     

Nanotechnology and health safety--toxicity and risk assessments of nanostructured materials on human health

The field of nanotechnology has recently emerged as the most commercially viable technology of this century because of its wide-ranging applications in our daily lives. Man-made nanostructured materials such as fullerenes, nanoparticles, nanopowders, nanotubes, nanowires, nanorods, nanofibers, quantum dots, dendrimers, nanoclusters, nanocrystals, and nanocomposites are globally produced in large quantities due to their wide potential applications, e.g., in skincare and consumer products, healthcare, electronics, photonics, biotechnology, engineering products, pharmaceuticals, drug delivery, and agriculture. Human exposure to these nanostructured materials is inevitable, as they can enter the body through the lungs or other organs via food, drink, and medicine and affect different organs and tissues such as the brain, liver, kidney, heart, colon, spleen, bone, blood, etc., and may cause cytotoxic effects, e.g., deformation and inhibition of cell growth leading to various diseases in humans and animals. Since a very wide variety of nanostructured materials exits, their interactions with biological systems and toxicity largely depend upon their properties, such as size, concentration, solubility, chemical and biological properties, and stability. The toxicity of nanostructured materials could be reduced by chemical approaches such by surface treatment, functionalization, and composite formation. This review summarizes the sources of various nanostructured materials and their human exposure, biocompatibility in relation to potential toxicological effects, risk assessment, and safety evaluation on human and animal health as well as on the environment.     

Peptide Nanophotonics: From Optical Waveguiding to Precise Medicine and Multifunctional Biochips

Optical waveguiding phenomena found in bioinspired chemically synthesized peptide nanostructures are a new paradigm which can revolutionize emerging fields of precise medicine and health monitoring. A unique combination of their intrinsic biocompatibility with remarkable multifunctional optical properties and developed nanotechnology of large peptide wafers makes them highly promising for new biomedical light therapy tools and implantable optical biochips. This Review highlights a new field of peptide nanophotonics. It covers peptide nanotechnology and the fabrication process of peptide integrated optical circuits, basic studies of linear and nonlinear optical phenomena in biological and bioinspired nanostructures, and their passive and active optical waveguiding. It is shown that the optical properties of this generation of bio‐optical materials are governed by fundamental biological processes. Refolding the peptide secondary structure is followed by wideband optical absorption and visible tunable fluorescence. In peptide optical waveguides, such a bio‐optical effect leads to switching from passive waveguiding mode in native α‐helical phase to an active one in the β‐sheet phase. The found active waveguiding effect in β‐sheet fiber structures below optical diffraction limit opens an avenue for the future development of new bionanophotonics in ultrathin peptide/protein fibrillar structures toward advanced biomedical nanotechnology.     

Biomolecular Piezoelectric Materials: From Amino Acids to Living Tissues

Biomolecular piezoelectric materials are considered a strong candidate material for biomedical applications due to their robust piezoelectricity, biocompatibility, and low dielectric property. The electric field has been found to affect tissue development and regeneration, and the piezoelectric properties of biological materials in the human body are known to provide electric fields by pressure. Therefore, great attention has been paid to the understanding of piezoelectricity in biological tissues and its building blocks. The aim herein is to describe the principle of piezoelectricity in biological materials from the very basic building blocks (i.e., amino acids, peptides, proteins, etc.) to highly organized tissues (i.e., bones, skin, etc.). Research progress on the piezoelectricity within various biological materials is summarized, including amino acids, peptides, proteins, and tissues. The mechanisms and origin of piezoelectricity within various biological materials are also covered.     

Nanodiamonds as nanomaterial for biomedical field

Recent advances in nanotechnology have attracted significant attention to nanodiamonds (NDs) in both industrial and research areas thanks to their remarkable intrinsic properties: large specific area, poor cytotoxicity, chemical resistance, magnetic and optical properties, ease of large-scale production, and surface reactivity make them suitable for numerous applications, including electronics, optics, sensors, polishing materials, and more recently, biological purposes. Growing interest in diamond platforms for bioimaging and chemotherapy is observed. Given the outstanding features of these particles and their ease of tuning, current and future applications in medicine have the potential to display innovative imaging applications and to be used as tools for monitoring and tracking drug delivery in vivo.