表面引发聚合新进展及应用

综述了近年来聚合物刷合成与应用方面的新进展.简要介绍了利用表面引发原子转移自由基聚合(SI-ATRP)制备聚合物刷的历程和重要进展.重点论述了通过电化学、光诱导以及牺牲阳极技术、仿生合成等发展了多种表面引发ATRP新方法,基于如何将聚合物从分子尺度过渡到微米尺度的思考,实现了多尺度聚合物刷结构的制备.简要综述了聚合物刷在以下3个方面的应用研究:(1)智能驱动,利用聚合物刷构象变化,实现微悬臂驱动、辅助放大的电驱动以及仿毛毛虫运动.(2)生物润滑,利用聚合物的环境响应行为实现了对摩擦系数的调控,并发展了球刷型润滑材料.(3)表面防污,表面接枝含离子液体官能团的聚合物刷,并与仿生技术相结合,利用化学组成和结构化协同效应,得到一系列高性能低毒海洋防污界面材料.     

Emerging Technology of Nanofiber-Composite Hydrogels for Biomedical Applications

Hydrogels and nanofibers have been firmly established as go-to materials for various biomedical applications. They have been mostly utilized separately, rarely together, because of their distinctive attributes and shortcomings. However, the potential benefits of integrating nanofibers with hydrogels to synergistically combine their functionalities while attenuating their drawbacks are increasingly recognized. Compared to other nanocomposite materials, incorporating nanofibers into hydrogel has the distinct advantage of emulating the hierarchical structure of natural extracellular environment needed for cell and tissue culture. The most important technological aspect of developing “nanofiber-composite hydrogel” is generating nanofibers made of various polymers that are cross-linked and short enough to maintain stable dispersion in hydrated environment. In this review, recent research efforts to develop nanofiber-composite hydrogels are presented, with added emphasis on nanofiber processing techniques. Several notable examples of implementing nanofiber-composite hydrogels for biomedical applications are also introduced.     

Recent Advances in the Synthesis and Biomedical Applications of Chain-End Functionalized Glycopolymers

Glycopolymers as multivalent clusters of carbohydrate derivatives have been proven effective tools in the study of carbohydrate-based biological processes and have shown great potential in biomedical applications. It has been found that the shape and size of glycopolymers, as well as the density and relative positioning of their glycan appendages, are very important regarding their effectiveness in bio-interactions. Recently, a variety of chain-end functionalized polymers have been explored for the preparation of structurally well-defined glycopolymers that have potential protein modification and microarray fabrication applications. This review summarizes recent advances in the synthesis and biomedical applications of chain-end functionalized glycopolymers.     

高分子基导电复合材料气敏响应机理研究

高分子基气敏导电材料是近年来发展起来的一种新型功能高分子复合材料.本文介绍了以炭黑(CB)为导电填充剂的复合传感材料的气敏响应机理的体积膨胀模型、结晶模型和氢键模型,并讨论了逾渗阀值、CB及聚合物微观结构与性能、以及CB与聚合物和溶剂三者之间相互作用等因素对该类材料气敏响应性的影响.     

Advances in Hybrid Composites for Photocatalytic Applications: A Review

Heterogeneous photocatalysts have garnered extensive attention as a sustainable way for environmental remediation and energy storage process. Water splitting, solar energy conversion, and pollutant degradation are examples of nowadays applications where semiconductor-based photocatalysts represent a potentially disruptive technology. The exploitation of solar radiation for photocatalysis could generate a strong impact by decreasing the energy demand and simultaneously mitigating the impact of anthropogenic pollutants. However, most of the actual photocatalysts work only on energy radiation in the Near-UV region (<400 nm), and the studies and development of new photocatalysts with high efficiency in the visible range of the spectrum are required. In this regard, hybrid organic/inorganic photocatalysts have emerged as highly potential materials to drastically improve visible photocatalytic efficiency. In this review, we will analyze the state-of-art and the developments of hybrid photocatalysts for energy storage and energy conversion process as well as their application in pollutant degradation and water treatments.     

More Than Meets the Eye in Bacterial Cellulose: Biosynthesis,Bioprocessing, and Applications in Advanced Fiber Composites

Bacterial cellulose (BC) nanofibers are one of the stiffest organic materials produced by nature. It consists of pure cellulose without the impurities that are commonly found in plant‐based cellulose. This review discusses the metabolic pathways of cellulose‐producing bacteria and the genetic pathways of Acetobacter xylinum. The fermentative production of BC and the bioprocess parameters for the cultivation of bacteria are also discussed. The influence of the composition of the culture medium, pH, temperature, and oxygen content on the morphology and yield of BC are reviewed. In addition, the progress made to date on the genetic modification of bacteria to increase the yield of BC and the large‐scale production of BC using various bioreactors, namely static and agitated cultures, stirred tank, airlift, aerosol, rotary, and membrane reactors, is reviewed. The challenges in commercial scale production of BC are thoroughly discussed and the efficiency of various bioreactors is compared. In terms of the application of BC, particular emphasis is placed on the utilization of BC in advanced fiber composites to manufacture the next generation truly green, sustainable and renewable hierarchical composites.     

Aggregation-Induced Emission: Recent Advances in Materials and Biomedical Applications

The concept of aggregation-induced emission (AIE) has opened new opportunities in many research fields. Motivated by the unique feature of AIE fluorogens (AIEgens), during the past decade, many AIE molecular probes and AIE nanoparticle (NP) probes have been developed for sensing, imaging and theranostic applications with excellent performance outperforming conventional fluorescent probes. This Review summarizes the latest advancement of AIE molecular probes and AIE NP probes and their emerging biomedical applications. Special focus is to reveal how the AIE probes are evolved with the development of new multifunctional AIEgens, and how new strategies have been developed to overcome the limitations of traditional AIE probes for more translational applications via fluorescence imaging, photoacoustic imaging and image-guided photodynamic/photothermal therapy. The outlook discusses the challenges and future opportunities for AIEgens to advance the biomedical field.     

Recent Advances in Glycerol Polymers: Chemistry and Biomedical Applications

Glycerol polymers are attracting increased attention due to the diversity of polymer compositions and architectures available. This article provides a brief chronological review on the current status of these polymers along with representative examples of their use for biomedical applications. First, the underlying chemistry of glycerol that provides access to a range of monomers for subsequent polymerizations is described. Then, the various synthetic methodologies to prepare glycerol‐based polymers including polyethers, polycarbonates, polyesters, and so forth are reviewed. Next, several biomedical applications where glycerol polymers are being investigated including carriers for drug delivery, sealants or coatings for tissue repair, and agents possessing antibacterial activity are described. Fourth, the growing market opportunity for the use of polymers in medicine is described. Finally, the findings are concluded and summarized, as well as the potential opportunities for continued research efforts are discussed.

     

Cellulose-Based Composites as Scaffolds for Tissue Engineering: Recent Advances

Today, numerous studies have focused on the design of novel scaffolds for tissue engineering and regenerative medicine applications; however, several challenges still exist in terms of biocompatibility/cytocompatibility, degradability, cell attachment/proliferation, nutrient diffusion, large-scale production, and clinical translation studies. Greener and safer technologies can help to produce scaffolds with the benefits of cost-effectiveness, high biocompatibility, and biorenewability/sustainability, reducing their toxicity and possible side effects. However, some challenges persist regarding their degradability, purity, having enough porosity, and possible immunogenicity. In this context, naturally derived cellulose-based scaffolds with high biocompatibility, ease of production, availability, sustainability/renewability, and environmentally benign attributes can be applied for designing scaffolds. These cellulose-based scaffolds have shown unique mechanical properties, improved cell attachment/proliferation, multifunctionality, and enhanced biocompatibility/cytocompatibility, which make them promising candidates for tissue engineering applications. Herein, the salient developments pertaining to cellulose-based scaffolds for neural, bone, cardiovascular, and skin tissue engineering are deliberated, focusing on the challenges and opportunities.     

单原子材料类酶催化及生物医学应用研究进展

纳米酶因其经济、 稳定、 性质可调和可循环利用等诸多优势, 成功地克服了天然酶在实际应用中的不足. 单原子材料的出现使得对纳米酶的研究迈入原子水平, 其较高的原子利用率、 独特的配位环境和较强的金属-载体相互作用为揭示纳米酶构效关系及调控类酶活性提供了可能. 本文总结了近年来单原子材料类酶催化的研究进展, 重点讨论了单原子材料类酶活性的调控策略和催化机理, 概述了单原子类酶材料在癌症治疗、 抗氧化治疗、 抗菌以及生物传感等方面的应用, 并对单原子类酶材料的发展前景进行了展望.     

Advances in Uniform Polymer Microspheres and Microcapsules: Preparation and Biomedical Applications

Microspheres and microcapsules have been widely used in biomedical field, such as delivery systems for drugs, vaccines. Uniform particle is required for precise drug delivery and disease treatment, since the particle diameter is a key factor which controls the pharmacokinetics and efficacy of loaded drug. However, there is no universal method to prepare uniform particles either from monomer or preformed polymer raw materials. We have developed two membrane emulsification techniques (MET) to prepare uniform particles with controllable size. In this review, we introduce two MET processes and their mechanisms, and how to develop MET to different emulsion systems to obtain various uniform microspheres and microcapsules with interesting morphologies. Then, the advantages of uniform particles on biomedical application results are focused. Finally, particle design and applications as “Chassis” to form synthetic vaccine are described. What is the most favorite and original chemistry developed in your research group? We clarified the mechanism for obtaining uniform microspheres and microcapsules in O/W, W/O and double emulsion systems, which enabled us to develop the technique to a universal technique, successfully preparing various uniform particles including hydrophobic, hydrophilic and composite functional particles, and leading to the original systematic studies on biomedical applications including “Synthetic Vaccine”. How do you get into this specific field? Could you please share some experiences with our readers? I started the research on preparation of nanospheres from my master course. At that time, I knew there were few universal methods to obtain uniform microspheres and microcapsules. So, after I became an assistant professor, I began to consider this scientific topic. How do you supervise your students? Our group motto is “Enjoy Science, Enjoy Work, Enjoy Life”. I tried to lead the students to like their research, and tried to find interesting results with students together based on their primary experimental results. What is the most important personality for scientific research? Pure, Passion, Perseverance. How do you keep balance between research and family? Work hard, and let my family know I am enjoyable and happy with my research, getting support and encouragement from family. Who influences you mostly in your life? My father. He always read books at the desk. He always gave me encouragement no matter happy or sad.     

水滑石(LDHs)及其衍生物在生物医药领域的研究进展

生物医学涉及到人类健康相关的多个领域:临床医疗、公共卫生、医药研发等多个方面.其中在医药研发领域,基于插层结构的纳米药物载体的研发已经成为重要发展方向之一.水滑石(LDHs)及其衍生物具有成本低、合成简单、载药高效、细胞膜透过率高、生物相容性好、易降解等优点,在生物医药领域得到了广泛关注.本文主要介绍了LDHs及其衍生物的制备方法,以及在抗菌治疗、生物成像和肿瘤治疗等方面的应用.此外,还简述了LDHs材料的规模化生产方法和现状,进一步分析了LDHs的实际应用前景.最后,对LDHs材料在生物医药领域的未来发展方向进行了展望.     

Polymer Nanocomposites in Sensor Applications: A Review on Present Trends and Future Scope

Polymers are crucial constituents of modern electronic devices. They can be used in their pristine, composite or nanocomposite forms for several domestic and industrial applications with innumerable unique possibilities. Polymer nanocomposites have gained wide theoretical interest and numerous practical applications in diverse fields of science and technology as they bestow the materials not only with virtuous processability but also with exceptional functionalities. It is evidenced that the electrical conductance of polymer nanocomposite is governed by the conductive filler networks within the polymer matrix. Hence, insignificant variation in the conductive networks can result in noteworthy variations in the output electric signal of polymer nanocomposite. Exploiting this stimuli-responsive performance of conductive networks to the physical parameters, polymer nanocomposites can be harnessed to fabricate novel sensitive sensors to detect vital physical parameters viz.strain/stress, pressure, temperature, solvent or vapor. Technical and phenomenological studies on polymer nanocomposites are still enduring.Advanced explanations are being sought but the mechanisms governing the formation of several polymer nanocomposites are still topics of debate in the material science community. Their in-depth investigation requires copious scientific work. This review analytically sketches the synthesis, microstructures, physiochemical properties and the underlying mechanisms for stimuli-responsiveness to the physical parameters of the polymer nanocomposites as well as their applications in various sensitive sensors and detectors. Thus, it became evocative for this review to focus on their processing methodologies, physiochemical physiognomies, classification and probable potentials of polymer nanocomposites.This review primarily presents the current literature survey on polymer composites and the gap areas in the study encourages the objective of the present review article. Finally, the status, perspectives and the advantages of specific polymer nanocomposites at present are summarized. The attention of this review is drawn to the present trends, challenges and future scope in this field of study. Finally, the vital concern and future challenge in utilizing the stimulus responsive behavior of polymer nanocomposites to design versatile sensors for real time applications are elaborately discussed.     

Photothermal Welding,Melting, and Patterned Expansion of Nonwoven Mats of Polymer Nanofibers for Biomedical and Printing Applications

We report a simple method for the photothermal welding of nonwoven mats of electrospun nanofibers by introducing a near‐infrared (NIR) dye such as indocyanine green. By leveraging the strong photothermal effect of the dye, the nanofibers can be readily welded at their cross points or even over‐welded (i.e., melted and/or fused together) to transform the porous mat into a solid film upon exposure to a NIR laser. While welding at the cross points greatly improves the mechanical strength of a nonwoven mat of nanofibers, melting and fusion of the nanofibers can be employed to fabricate a novel class of photothermal papers for laser writing or printing without chemicals or toner particles. By using a photomask, we can integrate photothermal welding with the gas foaming technique to pattern and then expand nonwoven mats into 3D scaffolds with well‐defined structures. This method can be applied to different combinations of polymers and dyes, if they can be co‐dissolved in a suitable solvent for electrospinning.     

共轭聚合物复合材料的结构和性能

对聚苯胺、聚吡啶等共轭聚合物与非导电聚合物材料的复合体系的结构和性能进行了综述。不同方法制备的复合材料在结构和性能上各有特点。一般共轭聚合物与非导电高分子材料相容性差、尤其是低极性高分了。     

多肽聚合物合成新方法及生物医学应用

多肽聚合物是以多肽为主链的合成聚合物,由于其固有的生物相容性和生物降解性,在生物医学领域展现出广阔的应用前景,然而多肽聚合物的高效、快速、简便合成仍然具有很大挑战。近年来随着合成化学的快速发展,基于α-氨基酸的N-羧基环内酸酐(NCA)开环聚合法制备多肽聚合物取得了突破性进展,合成了大量基于多肽聚合物的新型材料。本文首先介绍了NCA单体的合成机理及最新改进,然后重点介绍了近年来新发展的NCA开环聚合快速、高效制备多肽聚合物的不同引发或催化体系,最后简要介绍了多肽聚合物在抗菌剂、药物递送及组织工程等领域的应用,并提出了多肽聚合物材料在生物医学领域应用所面临的挑战。     

Self-Healing Polymer Composites: Prospects,Challenges, and Applications

Self-healing polymer composites possess the inherent ability to heal the damage event autonomically or non-autonomically with external intervention. These advanced materials can be commercialized if the challenges and limitations of different self-healing mechanisms are well known and considered. These include capsule-based healing systems, vascular healing systems, and intrinsic healing systems. To date, most of the reviews have studied and reported on different self-healing mechanisms including their response to impact, fatigue, and corrosion tests. This review focuses mostly on extrinsic and intrinsic self-healing polymer composites which have been reported during the past five years by comparing their healing efficiency, advantages, and challenges in the prospect of their future development as well as their possible applications across various industries such as aerospace, automobile, coating, electronics, energy, etc.     

Recent Advances in the Synthesis and Biomedical Applications of Heterocyclic NO-Donors

Nitric oxide (NO) is a key signaling molecule that acts in various physiological processes such as cellular metabolism, vasodilation and transmission of nerve impulses. A wide number of vascular diseases as well as various immune and neurodegenerative disorders were found to be directly associated with a disruption of NO production in living organisms. These issues justify a constant search of novel NO-donors with improved pharmacokinetic profiles and prolonged action. In a series of known structural classes capable of NO release, heterocyclic NO-donors are of special importance due to their increased hydrolytic stability and low toxicity. It is no wonder that synthetic and biochemical investigations of heterocyclic NO-donors have emerged significantly in recent years. In this review, we summarized recent advances in the synthesis, reactivity and biomedical applications of promising heterocyclic NO-donors (furoxans, sydnone imines, pyridazine dioxides, azasydnones). The synthetic potential of each heterocyclic system along with biochemical mechanisms of action are emphasized.     

Aggregation‐Induced Emission: Recent Advances in Materials and Biomedical Applications

The concept of aggregation‐induced emission (AIE) has opened new opportunities in many research fields. Motivated by the unique feature of AIE fluorogens (AIEgens), during the past decade, many AIE molecular probes and AIE nanoparticle (NP) probes have been developed for sensing, imaging and theranostic applications with excellent performance outperforming conventional fluorescent probes. This Review summarizes the latest advancement of AIE molecular probes and AIE NP probes and their emerging biomedical applications. Special focus is to reveal how the AIE probes are evolved with the development of new multifunctional AIEgens, and how new strategies have been developed to overcome the limitations of traditional AIE probes for more translational applications via fluorescence imaging, photoacoustic imaging and image‐guided photodynamic/photothermal therapy. The outlook discusses the challenges and future opportunities for AIEgens to advance the biomedical field.     

聚合物加工中微纳导电网络构筑及其传感器应用研究进展

设计和构筑有序微纳结构导电网络是聚合物基导电复合材料(CPC)加工中的关键问题,对于降低复合材料的逾渗阈值,提高其电导率和电阻响应灵敏性具有重要意义。本文综述了近年来CPC材料加工中利用双逾渗网络构筑法、隔离结构构筑法、气凝胶模板法、乳液模板法、3D打印法在聚合物基体中构建微纳导电网络及其在柔性传感器中的应用研究进展,并对未来CPC材料及其柔性传感器制备的加工新方法进行了展望。