Nanoreactors for Chemical Synthesis and Biomedical Applications

With the rapid development of nanoscience and nanotechnology, various types of functional nanoreactors have been designed for diverse applications. Here, the recent evolution of the rational design of nanoreactors for chemical synthesis and biomedical applications are briefly summarized and discussed. The presence of nanoreactors provides constrained space isolated from the surrounding environment. Scientists are committed to studying changes in chemical reactions when the reaction system is confined to the nanosized space. Nanoreactors accelerate the reaction rate and even change mechanism of some chemical reactions. Cells and organelles as natural nanoreactors are also discussed. The development of intracellular synthesis makes it possible to realize various applications in biomedicine. The challenges on the rational design of nanoreactors and perspectives are also discussed.     

Research Progress on Synthesis and Application of Cyclodextrin Polymers

Cyclodextrins (CDs) are a series of cyclic oligosaccharides formed by amylose under the action of CD glucosyltransferase that is produced by Bacillus. After being modified by polymerization, substitution and grafting, high molecular weight cyclodextrin polymers (pCDs) containing multiple CD units can be obtained. pCDs retain the internal hydrophobic-external hydrophilic cavity structure characteristic of CDs, while also possessing the stability of polymer. They are a class of functional polymer materials with strong development potential and have been applied in many fields. This review introduces the research progress of pCDs, including the synthesis of pCDs and their applications in analytical separation science, materials science, and biomedicine.     

光声成像技术的最新进展

光声成像技术是生物医学领域中新兴的无损检测技术,具有对比度高、分辨率好、穿透能力强等优点.本文介绍了光声成像技术近年来的进展状况,主要涉及成像探测方式的改进、成像速度的加快、成像分辨率的提高以及图像重构算法的发展等.以该项技术在现代临床诊断中的应用为例,描述了其在生物医学领域中应用范围的拓宽.最后,总结了该项技术现存的...     

Processing and Properties of Nanofibrous Bacterial Cellulose-Containing Polymer Composites: A Review of Recent Advances for Biomedical Applications

Abstract

Bacterial cellulose (BC) is an extracellular natural polymer produced by many microorganisms and its properties could be tailored via specific fabrication methods and culture conditions. There is a growing interest in BC derived materials due to the main features of BC such as porous fibrous structure, high crystallinity, impressive physico-mechanical properties, and high water content. However, pristine BC lacks some features, limiting its practical use in varied applications. Thus, fabrication of BC composites has been attempted to overcome these constraints. This review article overviews most recent advance in the development of BC composites and their potential in biomedicine including wound dressing, tissue engineering scaffolds, and drug delivery. Special emphasis is placed on the fabrication and applications of BC-containing nanofibrous composites for biomedical usage. It summarizes electrospinning of BC-based nanofibers and their surface modification with an outline on challenges and future perspective.     

从电子工业“脊梁”到全面开花的镓元素

镓是第一个根据化学元素周期律预言并在自然界中证实的元素，是室温下电导率和热导率均为最大的液态物质，镓在电子工业中得到了广泛应用，被誉为电子工业“脊梁”。近十几年来，镓的更多应用潜力被发掘出来，在电子工业、散热、增材制造、柔性机器、生物医学等领域均有重要的应用前景。     

Proteomic Profiling of the Human Fetal Multipotent Mesenchymal Stromal Cells Secretome

Secretome of multipotent mesenchymal stromal cells (MSCs) is actively used in biomedical applications such as alveolar bone regeneration, treatment of cardiovascular disease, and neurodegenerative disorders. Nevertheless, hMSCs have low proliferative potential and production of the industrial quantity of their secretome might be challenging. Human fetal multipotent mesenchymal stromal cells (FetMSCs) isolated from early human embryo bone marrow are easy to expand and might be a potential source for pharmaceutical substances production based on their secretome. However, the secretome of FetMSCs was not previously analyzed. Here, we describe the secretome of FetMSCs using LC-MALDI shotgun proteomics. We identified 236 proteins. Functional annotation of the identified proteins revealed their involvement in angiogenesis, ossification, regulation of apoptosis, and immune response processes, which made it promising for biomedical applications. The proteins identified in the FetMSCs secretome are involved in the same biological processes as proteins from previously described adult hMSCs secretomes. Nevertheless, many of the common hMSCs secretome components (such as VEGF, FGF, Wnt and TGF-β) have not been identified in the FetMSCs secretome.     

Targeted destruction of murine macrophage cells with bioconjugated gold nanorods

Gold nanorods manifest a readily tunable longitudinal plasmon resonance with light and consequently have potential for use in photothermal therapeutics. Recent work by others has shown how gold nanoshells and rods can be used to target cancer cells, which can then be destroyed using relatively high power laser radiation (∼1×10⁵ to 1×10¹⁰ W/m²). Here we extend this concept to demonstrate how gold nanorods can be modified to bind to target macrophage cells, and show that high intensity laser radiation is not necessary, with even 5×10² W/m² being sufficient, provided that a total fluence of ∼30 J/cm² is delivered. We used the murine cell line RAW 264.7 and the monoclonal antibody CD11b, raised against murine macrophages, as our model system and a 5 mW solid state diode laser as our energy source. Exposure of the cells labeled with gold nanorods to a laser fluence of 30 J/cm² resulted in 81% cell death compared to only 0.9% in the control, non-labeled cells.     

Metal–DNA Coordination-Driven Self-Assembly: A Conceptual Methodology to Expand the Repertoire of DNA Nanobiotechnology

The past several decades have witnessed a rapid revolution of DNA nanotechnology. DNA nanostructures are mainly synthesized with two approaches, by assembly of purely DNA-based nanostructures through complementary base pairing or grafting DNA onto nanoparticles (NPs). Despite the progress made, developing simple and universal methods for the synthesis of DNA nanoarchitectures with specific morphologies and functionalities is still a challenge. This article introduces the reader to a new biomimetic methodology that leads to the controlled synthesis of DNA nanoarchitectures based on metal–DNA coordination chemistry and, furthermore, demonstrates the broad biomedical applications of these functional materials. In particular, we highlight the coordination-driven 1) surface-functionalization of NPs with DNA molecules and 2) direct self-assembly of metal–DNA nanostructures. Finally, challenges and opportunities of this approach to develop nanobiotechnology are provided.     

磁性液体的合成及生物医学应用

本文综述了纳米磁粉的化学合成及磁性液体的一般制备方法及其磁性、磁流变性和磁熵热效应等在靶向给药、栓塞治疗、温热治疗上的应用。     

Visible light-curable polymers for biomedical applications

Photocurable systems, which offer advantages such as microfabrication and in situ fabrication, have been widely used as dental restorative materials. Because the visible light-curable (VLC) system causes no biological damage, it is popular as a dental material and is being investigated by many researchers for other medical applications. Here, the principle of the VLC system is explained and recent progress in key components including photoinitiators, monomers, macromers, and prepolymers is discussed. Finally, biomedical applications for drug delivery and soft tissue engineering are reviewed. Considering the recent development of VLC systems, its importance in the field of medical applications is expected to continue to increase in the future.