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Biodegradable conductive films are crucial for the sustainable development of wearable electronics. In this work, a flexible and degradable conductive film was prepared based on a carefully designed interface of polylactic acid (PLA) electrospun fibers and silver nanowires (AgNWs). The amphiphilic triblock copolymer was added to PLA solution for electrospinning, followed by solvent posttreatment to induce the hydrophilic block of the amphiphilic triblock copolymer to migrate to the fiber surface. Dopamine can be uniformly polymerized on the surface of hydrophilic PLA fibers, and the prepared PLA@PDA fiber film can form a good interface combination with AgNWs. The electrical conductivity of AgNWs/PLA@PDA flexible film can reach 258.5 S cm−1, showing obvious Joule heating effect and good mechanical properties. Degradation experiments showed that in phosphate buffered saline, the PLA molecular chain showed a dynamic equilibrium due to the scission and rearrangement of the ester groups and degraded slowly, while AgNWs/PLA@PDA degraded rapidly under alkaline conditions. Our study provides a simple and controllable method to prepare flexible degradable electronic films, which is expected to be applied to flexible wearable bioelectrodes. [ABSTRACT FROM AUTHOR]

The shapes of micro‐ and nano‐products have profound influences on their functional performances, which has not received sufficient attention during the past several decades. Electrohydrodynamic atomization (EHDA) techniques, mainly include electrospinning and electrospraying, are facile in manipulate their products' shapes. In this review, the shapes generated using EHDA for modifying drug release profiles are reviewed. These shapes include linear nanofibers, round micro‐/nano‐particles, and beads‐on‐a‐string hybrids. They can be further divided into different kinds of sub‐shapes, and can be explored for providing the desired pulsatile release, sustained release, biphasic release, delayed release, and pH‐sensitive release. Additionally, the shapes resulted from the organizations of electrospun nanofibers are discussed for drug delivery, and the shapes and inner structures can be considered together for developing novel drug delivery systems. In future, the shapes and the related shape–performance relationships at nanoscale, besides the size, inner structure and the related structure–performance relationships, would further play their important roles in promoting the further developments of drug delivery field. This article is categorized under:Therapeutic Approaches and Drug Discovery > Emerging Technologies [ABSTRACT FROM AUTHOR]

Hyper‐crosslinked polymers (HCPs) are a family of polymers that possess several desirable characteristics, including high specific surface area, excellent stability, tunable porous structures, and low‐cost reagents. As a result, HCPs have gained significant attention in the areas of gas storage, adsorption, catalysis, separation, and carbon precursors, exhibiting advanced performances in catalytic and energy‐related applications. Recently, researchers have explored the potential of HCPs in biomedical engineering. In this review, we discuss classical synthesis strategies and morphological assembly methods used to create HCPs with unique biological properties. We also highlight the latest advances in emerging biomedical areas of HCPs, such as drug delivery, antimicrobial, bioimaging, and biosensing. By providing various examples, we further discuss the correlations between the structures, morphologies, and enhanced biomedical properties of the HCPs. Finally, we summarize the key applications of HCPs and provide an outlook on the research direction to encourage further development of biomedically available HCPs. Overall, HCPs offer promising potential as a new class of materials for use in biomedical applications, and continued research in this field will lead to exciting discoveries and breakthroughs. [ABSTRACT FROM AUTHOR]

In this study, three kinds of electrohydrodynamic atomization (EHDA) processes (electrospraying, electrospinning, and coaxial electrospinning) are implemented to create hydroxypropyl methylcellulose (HPMC) based ultra‐thin products for providing the fast dissolution of a poorly water‐soluble drug ketoprofen (KET). An EHDA apparatus, characterized by a novel spinneret, is homemade for conducting the three processes. The three types of products are electrospun nanofibers E1, electrosprayed microparticles E2, and core‐shell nanofibers E3. SEM and TEM results indicate that they have the anticipated morphologies and inner structures. X‐ray diffraction and Fourier Transform Infrared results verify that KET is mainly amorphous in all the composites due to its fine compatibility with HPMC. In vitro dissolution tests demonstrate that the drug rapid release performances has an order of E3>E1>E2≫KET powders. The fast dissolution mechanisms are suggested and the advantages of the three products are compared. The super performance of E3 in furnishing the rapid release is attributed to a synergistic action of small size (of the shell thickness), high porosity, amorphous state of drug, and the solubility of HPMC. EHDA nanostructures can support the development of nano drug delivery systems (DDSs) through tailoring the spatial distribution of drug molecules within the nano products. [ABSTRACT FROM AUTHOR]

Core–shell structure is a concentric circle structure found in nature. The rapid development of electrospinning technology provides more approaches for the production of core–shell nanofibers. The nanoscale effects and expansive specific surface area of core–shell nanofibers can facilitate the dissolution of drugs. By employing ingenious structural designs and judicious polymer selection, specialized nanofiber drug delivery systems can be prepared to achieve controlled drug release. The synergistic combination of core–shell structure and materials exhibits a strong strategy for enhancing the drug utilization efficiency and customizing the release profile of drugs. Consequently, multi‐chamber core–shell nanofibers hold great promise for highly efficient disease treatment. However, little attention concentration is focused on the effect of multi‐chamber core–shell nanofibers on controlled release of drugs. In this review, we introduced different fabrication techniques for multi‐chamber core–shell nanostructures, including advanced electrospinning technologies and surface functionalization. Subsequently, we reviewed the different controlled drug release behaviors of multi‐chamber core–shell nanofibers and their potential needs for disease treatment. The comprehensive elucidation of controlled release behaviors based on electrospun multi‐chamber core–shell nanostructures could inspire the exploration of novel controlled delivery systems. Furthermore, once these fibers with customizable drug release profiles move toward industrial mass production, they will potentially promote the development of pharmacy and the treatment of various diseases. This article is categorized under:Therapeutic Approaches and Drug Discovery > Emerging Technologies [ABSTRACT FROM AUTHOR]

With the great demand for flexible self‐powered sensors and nanogenerators, polyvinylidene fluoride (PVDF) is widely investigated for outstanding piezoelectric and dielectric constant. In the pursuit for increasing β content, electrospinning is exhibited to be an effective method without external high voltage pooling or mechanical stretching and thus is considered a cost‐effective and simple method, because the molecular dipoles in the PVDF can be aligned during the process of electrospinning with high voltage field and stretching. The methods for improving piezoelectric characteristics are briefly introduced in this review, electrospinning fibers including uniaxial fibers, highly aligned fibers, core–shell fibers and Janus fibers are revealed, and research on theoretical modeling is carried out for efficiency in the design of piezoelectric nanogenerator. Last, studies on prospective applications based on electrospun PVDF and its copolymer PVDF‐TrFE, from sensors to smart skin, from energy harvesters to electronic textiles, are being conducted. [ABSTRACT FROM AUTHOR]

The wettability and adhesion of biological surfaces often depend on their periodically arranged hybrid micro–nano array structures. Various fabrication processes are designed to mimic biomimetic micro–nano array surfaces. This review summarizes the types of micro–nano array structures and analyzes fabrication methods based on top‐down and bottom‐up construction, including templating, etching, self‐assembly, and electrospinning/electrospraying. This review focuses on the shape reconfiguration of surface micro–nano array structures under physical stimuli, as well as the changes in material surface properties during the reconfiguration process. In addition, the applications of biomimetic micro–nano array composite surfaces in the fields of droplet transport, adhesion properties, sensors, and soft robotics are also discussed, and the current challenges and prospects in this field are identified. [ABSTRACT FROM AUTHOR]

Among different kinds of modified release profiles, sustained drug release (SDR) has received the most attention due to its capability to provide a "safe, efficacious, and convenient" drug delivery effect. Electrospun nanofibers have shown their popularity in this interdisciplinary field, as demonstrated by the first reports about SDRs on drug delivery applications of blended nanofibers and core–shell nanofibers. Along with the evolution of electrospinning from a single‐fluid blending process to coaxial, tri‐axial, side‐by‐side, and other multi‐fluid processes, more multi‐chamber nanostructures can be created through a single‐step straight forward manner. These multi‐chamber nanostructures can act as a powerful platform to support a wide variety of new strategies for the development of novel SDR nanomaterials. Thus, this review describes a combination history of electrospinning and SDR and its further development trend. After a summary of the presently popular multi‐chamber core–shell nanostructures, 15 strategies for furnishing SDR profiles are categorized and exemplified. The perspectives of electrospun multi‐chamber nanostructures for further promoting SDR are narrated. This article is categorized under:Therapeutic Approaches and Drug Discovery > Emerging Technologies [ABSTRACT FROM AUTHOR]

New nanostructure means new nanotechnology and nanoscience. The need of complex nanostructure‐based advanced functional nanomaterials has promoted the appearance of several kinds of multifluid electrospinning processes, such as tri‐axial electrospinning, quad‐fluid coaxial electrospinning, tri‐fluid side‐by‐side electrospinning, and coaxial electrospinning with a side‐by‐side core. These multifluid processes can greatly expand the capability of electrospinning in generating new types of nanostructures with different organization manner of the inner parts, and from both spinnable and unspinnable working fluids. The key elements for conducting a multifluid electrospinning lie in a well‐designed spinneret, compatibility of the working fluids, and special operational parameters. The complex nanostructures can be created through direct electrospinning of multiple fluids, through after‐treatment of the electrospun products, and through ingenious design of the components, compositions and their spatial distributions as well. This article provides a simple review on the most recent publications about the multifluid electrospinning processes and the corresponding complex nanostructures. This article is characterized under:Therapeutic Approaches and Drug Discovery > Emerging TechnologiesImplantable Materials and Surgical Technologies > Nanomaterials and Implants [ABSTRACT FROM AUTHOR]

ABSTRACT Fiber membrane adsorbent not only has the advantage of ease of handling, but also offers high specific surface area that can benefit the adsorption process when compared with powdered adsorbent. In this work, a poly(2-aminothiazole) (PAT)/cellulose acetate (CA) composite fiber membrane is prepared by a coaxial electrospinning process, and used as adsorbent for removing Hg(II) from water. The adsorption processes are investigated as functions of pH value, contact time and temperature. The results suggest that the Hg(II) adsorption is preferred to be conducted at pH 6.5 and the adsorption is a monolayer process through chemical interaction. The maximum adsorption capacity in theory is 177 mg/g at 298 K with a very low PAT percentage (6.5 wt %), which is much higher than that of the nanoparticle-type PAT through conversion. Desorption results exhibit excellent reusability of the composite fiber membrane. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44879. [ABSTRACT FROM AUTHOR]

A strategy is described to prepare epoxy resin nanofibers by combining coaxial electrospinning and traditional hot-curing processes. Core/sheath nanofibers with diameters of 480 ± 80 nm are prepared at flow rates of 0.1 and 2 mL h−1 for the core (20% w/v EP and 6% w/v curing agent in ethanol/acetone) and sheath (10% PVP in ethanol) fluids. After the curing of the nanofibers and selective removal of the sheath PVP, EP nanofibers with an average diameter of 210 ± 60 nm are obtained. ATR-FTIR analysis shows that the EP nanofibers display no obvious difference compared with an EP film cast from the core solution. The method presented allows to develop functional EP nanoproducts and to prepare heat-cured resin nanofibers. [ABSTRACT FROM AUTHOR]

Cover: A new strategy is proposed for the preparation of epoxy nanofibers from small molecules, which is based on the combination of coaxial electrospinning (for providing core/sheath nanofibers as templates), hot curing (for cross‐linking within the core part), and selective removal of the sheath polymer. Further details can be found in the article by X. Wang,* W.‐J. Zhang, D.‐G. Yu,* X.‐Y. Li, and H. Yang on page 664. [ABSTRACT FROM AUTHOR]