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Objective·To construct an electrospun short fibrous sponge (Sponge@GO) laden with graphene oxide (GO) for chronic wound healing.Methods·Two types of short fibrous sponges (Sponge and Sponge@GO) without and with GO were prepared by means of electrospinning, homogenizing, shaping and crosslinking with glutaraldehyde, respectively. The internal structures of the two sponges were observed with a scanning electron microscope (SEM), and their hydrophilic properties were observed via contact angle and water absorption rate. The biocompatibility of the sponge was verified by CCK-8 and live/dead staining. Twelve 6-week-old SD male rats were divided into control group, Sponge group and Sponge@GO group, with 4 rats in each group. The diabetes models were established by intraperitoneal injection of 1% streptozotocin solution, and three full-layer skin defects with a diameter of 1.0 cm were prepared on the back of each rat after modelling. Covering on the wound, the material was fixed with medical gauze. The control group was only covered with sterile gauze dressing. The wound healing rate was measured and calculated on Day 7 and 14, respectively, while hematoxylin-eosin (H-E) staining and Masson staining were performed on tissues within 0.5 cm around the wound to observe pathological changes. The angiogenesis was observed by α-smooth muscle actin (α-SMA) immunofluorescence staining on Day 14.Results·SEM observation showed that the fiber diameter of Sponge@GO was significantly thinner and the porosity increased. The two types of short fiber scaffolds basically reached the maximum water uptake within 10 min, but the Sponge@GO scaffold showed better water absorption performance. The water contact angle of Sponge@GO scaffold was significantly smaller than that of Sponge, and the difference was statistically significant (P=0.000). The results of CCK-8 method showed that on Day 3 and 5, the Sponge group had better cell proliferation compared with the control group (both P

Intraperitoneal sporadic tumor is a common and complicated syndrome in cancers, causing a high rate of death, and people find that intraperitoneal chemotherapy (IPC) can treat intraperitoneal sporadic tumors better than intravenous chemotherapy and surgery. However, the effectiveness and side effects of IPC are controversial, and the operation process of IPC is complicated. Herein, the injectable paclitaxel‐loaded (PTX‐loaded) electrospun short fibers are constructed through a series process of electrospinning, homogenizing, crosslinking, and subsequent polydopamine coating and folate acid (FA) modification. The evenly dispersed short fibers exhibited effective tumor cell killing and good injectable ability, which is convenient to use and greatly improved the complex operation procedure. Mussel‐like protein poly‐dopamine coating and FA modification endowed short fibers with the ability of targeted adhesion to tumors, and therefore the short fibers further acted as a kind of micro membrane that could release drugs to tumors at close range, maintaining local high drug concentration and prevent paclitaxel killing normal tissues. Thus, the target‐adhesive injectable electrospun short fibers are expected to be the potential candidate for cancer treatment, especially the intraperitoneal sporadic tumors, which are hard to treat by surgery or intravenous chemotherapy. [ABSTRACT FROM AUTHOR]

Electrospinning provides a facile route for generating fibers with diameters ranging from hundreds of nanometers to several micrometers. This technology has been widely explored in many biomedical areas including drug delivery systems (DDS), disease diagnosis and treatment, biosensing as well as tissue engineering. However, there are still existing challenges for electrospinning fibers in achieving complex regenerative or reconstructive processes through pure surface modification or simple drug loading. With the rise of nanotechnology, functional nanoparticles (NPs) made by various materials rapidly emerged in tissue engineering and regenerative medicine. Due to the objective size difference between NPs and electrospun fibers, doping NPs into electrospun nanofibers makes it possible to produce functional fibers having the inherent merits of both the guest NPs and the host fibers. In this review, we focus on the recent progress in preparing nanoparticle bearing electrospun hybrid fibers for biomedical applications. The organic, inorganic and mesoporous nanoparticles combined with electrospun nanofibers for different biological scenarios with several notable examples were systematically reviewed. Then, we finish with challenges and future perspectives of electrospun hybrid fiber materials for drug delivery and regenerative medicine. [ABSTRACT FROM AUTHOR]

With an increase in life expectancy and the popularity of high-intensity exercise, the frequency of tendon and ligament injuries has also increased. Owing to the specificity of its tissue, the rapid restoration of injured tendons and ligaments is challenging for treatment. This review summarizes the latest progress in cells, biomaterials, active molecules and construction technology in treating tendon/ligament injuries. The characteristics of supports made of different materials and the development and application of different manufacturing methods are discussed. The development of natural polymers, synthetic polymers and composite materials has boosted the use of scaffolds. In addition, the development of electrospinning and hydrogel technology has diversified the production and treatment of materials. First, this article briefly introduces the structure, function and biological characteristics of tendons/ligaments. Then, it summarizes the advantages and disadvantages of different materials, such as natural polymer scaffolds, synthetic polymer scaffolds, composite scaffolds and extracellular matrix (ECM)-derived biological scaffolds, in the application of tendon/ligament regeneration. We then discuss the latest applications of electrospun fiber scaffolds and hydrogels in regeneration engineering. Finally, we discuss the current problems and future directions in the development of biomaterials for restoring damaged tendons and ligaments. [ABSTRACT FROM AUTHOR]

Myocardial fibrosis and ventricular remodeling were the key pathology factors causing undesirable consequence after myocardial infarction. However, an efficient therapeutic method remains unclear, partly due to difficulty in continuously preventing neurohormonal overactivation and potential disadvantages of cell therapy for clinical practice. In this study, a rhACE2-electrospun fibrous patch with sustained releasing of rhACE2 to shape an induction transformation niche in situ was introduced, through micro-sol electrospinning technologies. A durable releasing pattern of rhACE2 encapsulated in hyaluronic acid (HA)—poly(L-lactic acid) (PLLA) core-shell structure was observed. By multiple in vitro studies, the rhACE2 patch demonstrated effectiveness in reducing cardiomyocytes apoptosis under hypoxia stress and inhibiting cardiac fibroblasts proliferation, which gave evidence for its in vivo efficacy. For striking mice myocardial infarction experiments, a successful prevention of adverse ventricular remodeling has been demonstrated, reflecting by improved ejection fraction, normal ventricle structure and less fibrosis. The rhACE2 patch niche showed clear superiority in long term function and structure preservation after ischemia compared with intramyocardial injection. Thus, the micro-sol electrospun rhACE2 fibrous patch niche was proved to be efficient, cost-effective and easy-to-use in preventing ventricular adverse remodeling. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Nanosilicates-based nanofibers were successfully prepared via electrospinning for bone tissue engineering. • Nanosilicates-based nanofibers promoted cell adhesion and osteogenic differentiation in vitro. • Nanosilicates-based nanofibers facilitated ectopic bone formation in vivo. Abstract Although growth factors and drugs (BMP-2, dexamethasone, etc.) have been widely used for bone tissue engineering, they have unignored limits such as adverse effects at high concentrations and easy inactivation in vivo. Accordingly, more osteoinductive supplements without side effects should be considered as alternatives in the design of bone tissue engineering scaffolds. Nanosilicate is a bioactive inorganic nanomaterial consisting of hydrous sodium lithium magnesium silicate, which is recently found to be safe and effective for bone induction. In this study, a range of organic/inorganic nanofibrous scaffolds with varied nanosilicate concentrations (0%, 1%, 5%, and 10% w/w to PCL matrix) were successfully fabricated via electrospinning. The tensile properties of the nanofibers were enhanced at low nanosilicate concentrations, and the incorporation of nanosilicates had no influence on cytocompatibility. Besides, in vitro osteogenesis experiments showed that nanosilicates-doped nanofibers were capable of inducing bone formation better than pure PCL nanofiber samples. More importantly, the results of histological and immunohistochemical assessments further revealed that the nanosilicates-enriched nanofibers had a significant potential of ectopic bone formation in vivo , while the pure PCL samples only induced limited osteogenic cues. All these results indicate that the nanosilicates-based organic/inorganic nanofibers may be potentially efficient for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Optimization of nanofiber surface properties can lead to enhanced tissue regeneration outcomes in the context of bone tissue engineering. Herein, we developed a facile strategy to decorate elctrospun nanofibers using extracellular matrix (ECM) in order to improve their performance for bone tissue engineering. Electrospun PLLA nanofibers (PLLA NF) were seeded with MC3T3-E1 cells and allowed to grow for two weeks in order to harvest a layer of ECM on nanofiber surface. After decellularization, we found that ECM was successfully preserved on nanofiber surface while maintaining the nanostructure of electrospun fibers. ECM decorated on PLLA NF is biologically active, as evidenced by its ability to enhance mouse bone marrow stromal cells (mBMSCs) adhesion, support cell proliferation and promote early stage osteogenic differentiation of mBMSCs. Compared to PLLA NF without ECM, mBMSCs grown on ECM/PLLA NF exhibited a healthier morphology, faster proliferation profile, and more robust osteogenic differentiation. Therefore, our study suggests that ECM decoration on electrospun nanofibers could serve as an efficient approach to improving their performance for bone tissue engineering. [ABSTRACT FROM AUTHOR]

Distal necrosis of random skin flap is always clinical problematic in plastic surgery. The development of 3D functional vascular networks is fundamental for the survival of a local random skin flap. Herein, an effective technique on constructing 3D fibrous scaffolds for accelerated vascularization is demonstrated using a photocrosslinkable natural hydrogel based on gelatin methacryloyl (GelMA) by electrospinning. It is found that the ultraviolet (UV) photocrosslinkable gelatin electrospun hydrogel fibrous membranes exhibit soft adjustable mechanical properties and controllable degradation properties. Furthermore, it is observed that the optimized hydrogel scaffolds can support endothelial cells and dermal fibroblasts adhesion, proliferation, and migration into the scaffolds, which facilitates vascularization. Importantly, a rapid formation of tubes is observed after 3 d seeding of endothelial cells. After GelMA fibrous scaffold implantation below the skin flap in a rat model, it is found that the flap survival rate is higher than the control group, and there is more microvascular formation, which is potentially beneficial for the flap tissue vascularization. These data suggest that GelMA hydrogels can be used for biomedical applications that require the formation of microvascular networks, including the development of complex engineered tissues. [ABSTRACT FROM AUTHOR]

Abstract: Vasospasm is a common post-operative complication after vascular anastomosis. Currently, the main treatment is a local injection of antispasmodic drugs. However, this method has a high rate of relapse and is subject to a large degree of individual variation, and repeated injections cause additional pain for patients. In this study, we developed highly flexible and rapidly degradable papaverine-loaded electrospun fibrous membranes to be wrapped around vascular suturing to prevent vasospasm. Poly-l-lactic acid/polyethylene glycol (PLLA/PEG) electrospun fibers containing papaverine maintained a high degree of flexibility and could withstand any folding, and are therefore suitable for wrapping vascular suturing. A rapid release of papaverine, between 2 and 7days, was achieved by adjusting the proportions of PEG and PLLA. PLLA electrospun fibers containing 40% PEG (PLLA-40%) could control drug release and polymer degradation most effectively during the first 2weeks post-operation. Testing using an in vivo rabbit model showed that PLLA-40% fibrous membranes produced significant antispasmodic effect without observable inflammation or hyperplasia, and the fibrous membranes were ideally biodegradable, with no impact on regional blood flow, pressure, vessel diameter or surrounding tissue hyperplasia. Therefore, papaverine-loaded electrospun fibrous membranes show the potential to greatly reduce post-operative vasospasm and maintain regular vascular morphology during antispasmodic therapy. [Copyright &y& Elsevier]

Abstract: Clinically, hypertrophic scarring (HS) is a major concern for patients and has been a challenge for surgeons, as there is a lack of treatments that can intervene early in the formation of HS. This study reports on a Chinese drug, 20(R)-ginsenoside Rg3 (GS-Rg3), which can inhibit in vivo the early formation of HS and later HS hyperplasia by inducing the apoptosis of fibroblasts, inhibiting inflammation and down-regulating VEGF expression. Implantable biodegradable GS-Rg3-loaded poly(l-lactide) (PLA) fibrous membranes were successfully fabricated using co-electrospinning technology to control drug release and improve drug utilization. The in vivo releasing time of GS-Rg3 lasts for 3months, and the drug concentration released in rabbits can be controlled by varying the drug content of the electrospun fibers. Histological observations of HE staining indicate that GS-Rg3/PLA significantly inhibits the HS formation, with obvious improvements in terms of dermis layer thickness, epidermis layer thickness and fibroblast proliferation. The results of immunohistochemistry staining and Masson’s trichrome staining demonstrate that GS-Rg3/PLA electrospun fibrous membranes significantly inhibit HS formation, with decreased expression of collagen fibers and microvessels. VEGF protein levels are much lower in the group treated with GS-Rg3/PLA eletrospun membranes compared with other groups. These results demonstrate that GS-Rg3 is a novel drug, capable of inhibiting the early formation of HS and later HS hyperplasia. GS-Rg3/PLA electrospun membrane is a very promising new treatment for early and long-term treatment of HS. [Copyright &y& Elsevier]

This paper explores the application potential of a biodegradable PLLA/chitosan electrospun composite membrane for guided periodontal tissue regeneration which in addition serves as a fibroblast barrier. Electrospinning was applied to fabricate the PLLA membrane and aminolysis method was applied to graft chitosan on its surface. The morphology of the PLLA/chitosan membrane was observed by SEM. The surface chemical composition was analyzed by XPS. The appearance of N 1 s peak in XPS demonstrated the successful grafting of chitosan on the PLLA electrospin membrane. After the modification, the water contact angle decreased from 136.9 ± 2.18° to 117.0 ± 2.10°, representing an improved hydrophilicity of the membrane. The bioactivity of the membrane was analyzed by XPS after soaking in SBF. The deposits had a Ca/P ratio of 1.6, indicating the hydroxyapatite formation on PLLA/chitosan membrane. The degradation rate was determined by measuring mass loss after immersion in PBS at different time periods. Compared to pure PLLA electrospun membrane which was almost non-degradable, the degradation rate of PLLA/chitosan composite membrane was up to 20 % in 6 weeks while maintaining its basic architecture to keep supporting the regenerated tissue. Live-dead cell staining of MC3T3 E1 cells cultured on the surface of the membrane showed a good biocompatibility of the PLLA/chitosan membrane. Furthermore, fibroblast cell line NIH 3T3 was cultured on surface of the membrane for the evaluation of cell penetration. The result demonstrated that the membrane worked as a fibroblast barrier to minimize the unfavorable effect of fibroblasts on periodontal tissue regeneration. Therefore, this electrospun PLLA/chitosan composite membrane has more potential for clinical application compared to old generation regeneration membrane with both suitable degradation rate and non-fibroblast penetration property. [ABSTRACT FROM AUTHOR]

Electrospun fibrous membranes have been used frequently in biomedical applications, but their simultaneous use as antibacterial agents and in the prevention of cell adhesion on repaired tendons after injury has not been investigated. In this study, silver-nanoparticle (SN)-loaded poly( L-lactide) (PLLA) fibrous membranes were prepared by the electrospinning of SNs into PLLA fibers. Micrograph results showed that these membranes were composed of electrospun fibers and that the fibers were incorporated with SNs. From the results of X-ray diffraction and thermogravimetry, we concluded that the SNs were physically mixed into the fibers at the desired content. The mechanical properties were not significantly changed. The preliminary antibacterial effects on Staphylococcus epidermidis and Staphylococcus aureus and the synergistic antiproliferative effects of the SN-loaded PLLA fibrous membranes were observed. Taken together, these results demonstrate that SNs can be directly loaded onto a biodegradable PLLA fibrous membrane via electrospinning to achieve proper material properties with preliminary potential as antibacterial antiadhesion barriers for tendon injury. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Abstract: In benign esophageal strictures, inflammation reaction and tissue hyperplasia after stent placement greatly limit the stent retention time and affect subsequent scar formation, which is one of the main influences on long-term recurrence rate. A newly developed biodegradable electrospun drug-fiber-coated stent (DFCS) was fabricated to inhibit inflammation and scar formation. The electrospun paclitaxel/poly(ε-caprolactone) (PCL) fibers integrally covered the bare stent using the rotating collection method. The paclitaxel entrapment did not significantly affect the physical properties of electrospun PCL fibrous membranes. The mechanical results demonstrated that electrospun fibers containing paclitaxel covering the stent maintained the original mechanical characteristics of the stent, and no membrane tearing or ablation was observed after hundreds of repeated compressions. Paclitaxel release profiles were controlled mainly via diffusion of drug through the drug content, and stable release of paclitaxel continued up to 32days at pH 4.0. Higher inhibition of smooth muscle cell proliferation rates was observed on fibrous membranes with higher paclitaxel content. DFCS showed a significant decrease in tissue inflammation and collagen fiber proliferation, and was easily removed from the esophageal part, which had almost no damage to the tissues in the dog model. Therefore, DFCSs may have great potential to markedly attenuate stent-induced inflammation and scar formation in esophageal stenosis therapy. [Copyright &y& Elsevier]

Abstract: Physical barriers such as electrospun fibrous membranes are potentially useful in preventing peritendinous adhesions after surgery. However, inflammatory responses caused by degradation of barrier materials remain a major challenge. This study aimed to fabricate electrospun composite fibrous membranes based on drug-loaded modified mesoporous silica (MMS) and poly (l-lactic acid) (PLLA). Using a co-solvent-based electrospinning method ibuprofen (IBU)-loaded MMS was successfully and uniformly encapsulated in the PLLA fibers. The electrospun PLLA–MMS–IBU composite fibrous membranes showed significantly lower initial burst release (6% release in the first 12h) compared with that of electrospun PLLA–IBU fibrous membranes (46% release in the first 12h) in in vitro release tests. Moreover, the release from PLLA–MMS–IBU was also for significantly longer than that from PLLA–IBU (100 vs. 20days). In animal studies both PLLA–IBU and PLLA–MMS–IBU showed improved anti-adhesion properties and anti-inflammatory effects compared with PLLA fibrous membrane alone 4weeks after implantation. Further, animals implanted with PLLA–MMS–IBU for 8weeks showed the lowest inflammation and best recovery compared with those implanted with PLLA–IBU and PLLA, most likely as a result of its long-term IBU release profile. Therefore, this study provides a platform technique for fabricating fibrous membranes with long-term sustained drug release characteristics which may function as a novel carrier for long-term anti-inflammation and anti-adhesion to prevent peritendinous adhesions. [Copyright &y& Elsevier]

Fabricating fibrous electrospun scaffolds with controllable fiber-arrangement have gained an increasing attention in the field of tissue engineering. In this study, the composite patterned D,L-poly(lactic acid)/poly(ε-caprolactone) (PDLLA/PCL) scaffolds were fabricated via electrospinning for the first time, and the order degree and contractibility of patterned composite scaffolds with different PDLLA/PCL ratios were further investigated. The results showed that the order degree of the pattern and in vitro shrinkage behaviors of PDLLA/PCL electrospun mats could be finely tuned by controlling blending ratios. The PDLLA/PCL electrospun mats with the ratio 50/50 showed the most balanced properties with controllable pattern structure and appropriate dimensional stability, and they might be a suitable candidate for tissue engineering application. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

Abstract: The methods of co-electrospinning and surface hydrolysis have been used for improving hydrophilicity of Poly(l-lactide) (PLLA), while most of them resulted in high shrinkage and changed mechanical properties of bulk polymers. In this study, we modify PLLA electrospun scaffolds by grafting chitosan by aminolysis technology. The results showed that the amount of grafted chitosan on fibrous scaffolds could be adjusted by controlling aminolysis time, and the hydrophilicity of scaffolds was dependent on the amount of grafted chitosan. Water contact angle of scaffolds were changed from 138.3° to 0°. Characteristic analysis of scaffolds indicated that aminolysis method did not affect the porous structure. The density of the modified scaffolds was between 0.48 and 0.54 g/cm3 and the tensile strength was between 3.24 and 3.45 MPa, which were statistically not different as compared to unmodified scaffolds (P > 0.05). The statistical analysis of the cell culture results showed that the cell proliferation on chitosan modified PLLA scaffolds were significantly improved as compared to that on the unmodified PLLA scaffolds (P < 0.05). All of results suggest that the aminolysis method is a convenient and effective mild chemical treatment method to improve hydrophilicity and cell biocompatibility of PLLA electrospun fibrous scaffolds for tissue engineering without sacrificing other properties. [Copyright &y& Elsevier]

Well-aligned and highly ordered architectures are always required in many fields, such as tissue engineering, electronics, and preparation of composite materials. In this study, electrospun mats with well-aligned fibers and various fiber assemblies were successfully fabricated by electrospinning of poly(vinylbutyral) (PVB)/inorganic salt solution under the optimal salt condition. Then, the effect of inorganic salts on the degree of electrospun fiber alignment was comprehensively investigated, and the results indicated that the viscosity and conductivity of the solutions were the key factors influencing the degree of fiber alignment. It was expected that this simple and feasible method could be helpful for the fabrication of the well-aligned electrospun fibers and various fiber assemblies. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 [ABSTRACT FROM AUTHOR]

Abstract: Controlled nucleation and growth of hydroxyapatite (HA) crystals on electrospun fibers should play important roles in fabrication of composite scaffolds for bone tissue engineering, but no attempt has been made to clarify the effects of chemical group densities and the cooperation of two and more groups on the biomineralization process. The aim of the current study was to investigate into HA nucleation and growth on electrospun poly(dl-lactide) fibers functionalized with carboxyl, hydroxyl and amino groups and their combinations. Electrospun fibers with higher densities of carboxyl groups, combination of hydroxyl and carboxyl groups with the ratio of 3/7, and combination of amino, hydroxyl and carboxyl groups with the ratio of 2/3/5 were favorable for HA nucleation and growth, resulting in higher content and lower crystal size of formed HA. Carboxyl groups were initially combined with calcium ions through electrostatic attraction, and the introduction of hydroxyl groups could modulate the distance between carboxyl groups. The introduction of amino groups may lead to the inner ionic bonding with carboxyl groups, but can accelerate phosphate ions to form HA through a chelate ring with the calcium ion and carbonyl oxygen. The biological evaluation indicated that the mineralized scaffolds acted as an excellent cell support to maintain desirable cell–substrate interactions, to provide favorable conditions for cell proliferation and to stimulate the osteogenic differentiation. [Copyright &y& Elsevier]

The electrospinning technique, which was invented about 100 years ago, has attracted more attention in recent years due to its possible biomedical applications. Electrospun fibers with high surface area to volume ratio and structures mimicking extracellular matrix (ECM) have shown great potential in tissue engineering and drug delivery. In order to develop electrospun fibers for these applications, different biocompatible materials have been used to fabricate fibers with different structures and morphologies, such as single fibers with different composition and structures (blending and core-shell composite fibers) and fiber assemblies (fiber bundles, membranes and scaffolds). This review summarizes the electrospinning techniques which control the composition and structures of the nanofibrous materials. It also outlines possible applications of these fibrous materials in skin, blood vessels, nervous system and bone tissue engineering, as well as in drug delivery. [ABSTRACT FROM AUTHOR]

Abstract: This study is derived from the innate concerns of electrospun poly(DL-lactide) (PDLLA) fibers as tissue engineering scaffolds: hydrophobic surface, surface erosion and dimensional shrinkage, which are not favorable to trigger the initial adhesion and further growth and population of cells. Blending electrospinning of PDLLA and poly(ethylene glycol) (PEG) with different PEG contents was evaluated for optimal tissue engineering scaffolds. The surface hydrophilicity was improved, and the degradation patterns of PDLLA/PEG mats changed from surface erosion to bulk degradation with the increase in PEG contents. The dimensional shrinkage was alleviated through the formation of crystal regions of PEG in the fiber matrix. The PDLLA/PEG fibrous mats were slightly weakened with the increase in the PEG contents, but a significant decrease in the tensile strength could be found for those with PEG contents of over 40%. Human dermal fibroblasts (HDFs) interacted and integrated well with the surrounding fibers containing 20 and 30% PEG, which provided significantly better environment for biological activities of HDFs than electrospun PDLLA mats. It indicated that electrospun mats containing 30% PEG exhibited the most balanced properties, including moderately hydrophilic surface, minimal dimensional changes, adaptable bulk biodegradation pattern and enhancement of cell penetration and growth within fibrous mats. [Copyright &y& Elsevier]

Abstract: The local delivery and controllable release profiles make electrospun ultrafine fibers as potential implantable drug carriers and functional coatings of medical devices. Till date there is no literature report on drug delivery from acid-labile electrospun fibers, whose degradation and drug release behaviors respond to the local pathological pH environment. Acid-labile groups have been incorporated into nonbiodegradable backbones as crosslinkers or linkers of the side chains. A novel strategy was developed in this study to synthesize acid-labile polymers by introducing acetal groups into biodegradable backbone of poly(dl-lactide)–poly(ethylene glycol). In vitro release study showed that the total amount of drug released from acid-labile polymeric fibers was accelerated on account of pH-induced structural and morphological changes of fibrous mats and the degradation of matrix polymers, and the burst release was significant higher for polymers with higher contents of acid-labile segments. During the investigational period, almost no molecular weight reduction and mass loss was detected in neutral buffer solutions, but the degradation was enhanced in acid buffers with a two-stage degradation profile. Surface erosion mechanism was initially detected for fibrous mats with distinct fiber morphologies, and bulk degradation was determined during the following incubation for polymeric films resulting from the morphological changes. [Copyright &y& Elsevier]

Abstract: Degradation profiles and surface wettability are critical for optimal application of electrospun fibrous mats as drug carriers, tissue growth scaffolds and wound dressing materials. The effect of surface morphologies and chemical groups on surface wettability, and the resulting matrix degradation profiles were firstly assessed for electrospun poly(d,l-lactide) (PDLLA) and poly(d,l-lactide)-poly(ethylene glycol) (PELA) fibers. The air entrapment between the fiber interfaces clarified the effects of various surface morphologies on the surface wettability. Chemical groups with lower binding energy were enriched on the fiber surface due to the high voltage of the electrospinning process, and a surface erosion pattern was detected in the degradation of electrospun PDLLA fibers, which was quite different from the bulk degradation pattern for other forms of PDLLA. Contributed by the hydrophilic poly(ethylene glycol) segments, the degradation of electrospun PELA fibers with hydrophobic surface followed a pattern different from surface erosion and typical bulk degradation. [Copyright &y& Elsevier]

Nanocrystalline hydroxyapatite assembled hollow fibers (NHAHF) in the membrane form were fabricated by combining the electrospinning technique and the hydrothermal method. This novel hierarchical tubular structure of hydroxyapatite exhibited excellent protein loading capacity and long-term sustained release property. [ABSTRACT FROM AUTHOR]

Fully simulating the components and microstructures of soft tissue is a challenge for its functional regeneration. A new aligned hydrogel microfiber scaffold for spinal cord regeneration is constructed with photocrosslinked gelatin methacryloyl (GelMA) and electrospinning technology. The directional porous hydrogel fibrous scaffold consistent with nerve axons is vital to guide cell migration and axon extension. The GelMA hydrogel electrospun fibers soak up water more than six times their weight, with a lower Young's modulus, providing a favorable survival and metabolic environment for neuronal cells. GelMA fibers further demonstrate higher antinestin, anti‐Tuj‐1, antisynaptophysin, and anti‐CD31 gene expression in neural stem cells, neuronal cells, synapses, and vascular endothelial cells, respectively. In contrast, anti‐GFAP and anti‐CS56 labeled astrocytes and glial scars of GelMA fibers are shown to be present in a lesser extent compared with gelatin fibers. The soft bionic scaffold constructed with electrospun GelMA hydrogel fibers not only facilitates the migration of neural stem cells and induces their differentiation into neuronal cells, but also inhibits the glial scar formation and promotes angiogenesis. Moreover, the scaffold with a high degree of elasticity can resist deformation without the protection of a bony spinal canal. The bioinspired aligned hydrogel microfiber proves to be efficient and versatile in triggering functional regeneration of the spinal cord. Inspired by the intricate physiological anatomy and unique physical properties of the spinal cord, a new aligned hydrogel microfiber scaffold is constructed with hydrogel and electrospinning for the repair of spinal cord injury. [ABSTRACT FROM AUTHOR]

In article number 1806899, Bruno Sarmento, Wenguo Cui, Liang Chen, and co‐workers construct a new aligned hydrogel microfiber scaffold, which is inspired by the intricate physiological anatomy and unique physical properties of the spinal cord, using hydrogel and electrospinning for treating spinal cord injuries. [ABSTRACT FROM AUTHOR]

Recently, it has been reported that Hydrogen sulfide (H 2 S) plays an anti-atherosclerotic role both in vitro and in vivo . Its deficiency leads to early development and progression of atherosclerosis especially. This study was designed to investigate S-propargyl-cysteine (SPRC), an H 2 S modulator, as well as its effect on the progression of endothelial-protective effect in oxidized Low-Density Lipoprotein (oxLDL) induced apoptosis in Human umbilical vein endothelial cells (HUVECs) and underlying mechanisms. Implantable biodegradable SPRC-loaded poly (l-lactide) (PLA) fibrous membranes were successfully fabricated using co-electrospinning technology to control drug release and improve drug utilization. Polymeric drug delivery systems are capable of improving therapeutic efficacy, reducing toxicity, and enhancing patient compliance due to their controlled delivery of drugs. Electrospinning is a remarkably simple and powerful technique used to generate polymeric fibers at a sub-micrometer scale (ranging from approximately 50 nm to several μm). Biodegradable electrospun poly (l-lactide) (PLA, FDA) was demonstrated their potential as effective carriers for drug delivery. Implantable biodegradable SPRC-loaded poly (l-lactide) (PLA) fibrous membranes were successfully fabricated using co-electrospinning technology to control drug release and improve drug utilization. The in vivo releasing time of SPRC lasted for 72 h, and the drug concentration released in HUVECs could be controlled by varying the drug content of the electrospun fibers. 3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) and 5,5′,6,6′-Tetrachloro-1,1′,3,3′- tetraethyl-imidacarbocyanine iodide (JC-1) assays indicated that SPRC/PLA electrospun fibrous membranes significantly inhibited the HUVECs apoptosis. In addition, Marginal changes in the lipid parameters were found in the SPRC/PLA electrospun fibrous membranes-treated HUVECs, with advanced glycation end products (AGES), triglyceride (TG) and high-density lipid cholesterol (HDL-C) elevation reduction at the 6% dose. These findings suggested that SPRC/PLA electrospun membrane is a very promising new treatment for early and long-term treatment of atherosclerotic vascular disease. [ABSTRACT FROM AUTHOR]

Abstract: In situ grown hydroxyapatite (HA) within electrospun poly(dl-lactide) (PDLLA) fibers were initially investigated as potential tissue engineering scaffolds with respect to the mechanical performances, biomineralization capability, degradation behaviors, cell growth and differentiation profiles. The tensile strength and Young’s moduli of in situ grown composites (IGC) were 8.2 ± 1.1 and 63.5 ± 5.6 MPa, respectively, which were significantly higher than those of blend electrospun composites (BEC) with 25.2% of HA inoculation. The interactions between HA and matrix polymers were approved by the red-shifts of Cing and OH– stretching modes and the increases in glass transition temperatures of fibrous composites. The localization of apatite phase on the fiber surface improved the biomineralization capability and enhanced the morphological stability of the fibers and fibrous mats even when the degradation of matrix polymers was detected. The cell viability and alkaline phosphatase levels were significantly higher for composites IGC, indicating favorable scaffolds for cell proliferation and osteogenic differentiation. [ABSTRACT FROM AUTHOR]

[Display omitted] Bone regenerative engineering provides a great platform for bone tissue regeneration covering cells, growth factors and other dynamic forces for fabricating scaffolds. Diversified biomaterials and their fabrication methods have emerged for fabricating patient specific bioactive scaffolds with controlled microstructures for bridging complex bone defects. The goal of this review is to summarize the points of scaffold design as well as applications for bone regeneration based on both electrospinning and 3D bioprinting. It first briefly introduces biological characteristics of bone regeneration and summarizes the applications of different types of material and the considerations for bone regeneration including polymers, ceramics, metals and composites. We then discuss electrospinning nanofibrous scaffold applied for the bone regenerative engineering with various properties, components and structures. Meanwhile, diverse design in the 3D bioprinting scaffolds for osteogenesis especially in the role of drug and bioactive factors delivery are assembled. Finally, we discuss challenges and future prospects in the development of electrospinning and 3D bioprinting for osteogenesis and prominent strategies and directions in future. [ABSTRACT FROM AUTHOR]

Electrospun fibrous membranes provide suitable physical anti-adhesion barriers for reducing tissue anti-adhesion following surgery. However, often during the biodegradation process, these barriers trigger inflammation and cause a foreign body reaction with subsequent decrease in anti-adhesion efficacy. Here, a facile strategy comprising the incorporation of ibuprofen (IBU) into implantable membranes and its sustained release was proposed in order to improve anti-adhesion effects and neurological outcomes, namely to prevent failed back surgery syndrome (FBSS). The combination of free IBU and a newly synthetized polymeric prodrug of IBU, namely poly(hydroxyethyl methacrylate) with ester-linked IBU, was successfully used in order to reduce initial burst drug release and provide sustained drug release from fibrous membranes throughout several weeks. Such release profile was shown useful in preventing both acute and chronic inflammation in rats following laminectomy and membrane implantation. Moreover, histological analysis provided evidence of an excellent anti-adhesion effect, while associated neurological deficits were effectively reduced. Furthermore, the assessment of macrophage density, neovascularization, and related gene expression at the lesion site revealed that a sustained anti-inflammatory effect was achieved with the IBU-loaded proposed fibrous membranes. Results suggested that the COX2 pathway plays an important role in the development epidural fibrosis and arachnoiditis. Overall, this study provided evidence that precisely engineered IBU-loaded electrospun fibrous membranes may be useful in preventing FBSS and able to potentially impact the outcome of patients undergoing spine surgery. [ABSTRACT FROM AUTHOR]

As tumor microenvironment becoming more and more important in tumor study, the acid pH around or in solid tumors drew lots of attentions. And the progress of drug delivery systems made the responsive-release possible. This time, we fabricated a new-type composite electrospun poly (L-lactide) (PLLA) fibrous scaffolds, that blent with the mesoporous silica particles (MSNs). Further more, we used sodium bicarbonate (SB) as acid sensitive agent which was wrapped inside the MSNs. And doxorubicin (DOX) was also wrapped into MSNs in order to achieve a sustained release to inhibit tumors in mice, which mimicked the remnant breast cancer with surgery. In vitro experiments proved the characteristic of pH-responsive release of the composite fibrous scaffold. In vivo results showed that these composite fibers could induce obvious apoptosis and necrosis over 10 weeks. Further, the cancer-kill effects were also confirmed by the decreased level of Bcl-2 and TNF-α, while increased Bax and caspase-3 expression levels. Altogether, the results indicated that the composite drug delivery system as a local implantable scaffold could effectively kill cancer cells in a long term with pH-sensitivity after the tumor resection. [ABSTRACT FROM AUTHOR]

To balance intrinsic and extrinsic healing during tendon repair is challenging in tendon surgery. We hypothesized that by mediating apoptotic gene and collagen synthesis of exogenous fibroblasts, the adhesion formation induced by extrinsic healing could be inhibited. With the maintenance of intrinsic healing, the tendon could be healed with proper function with no adhesion. In this study, we loaded hydrophilic mitomycin-C (MMC) into hyaluronan (HA) hydrosols, which were then encapsulated in poly(L-lactic acid) (PLLA) fibers by micro-sol electrospinning. This strategy successfully provided a controlled release of MMC to inhibit adhesion formations with no detrimental effect on intrinsic healing. We found that micro-sol electrospinning was an effective and facile approach to incorporate and control hydrophilic drug release from hydrophobic polyester fibers. MMC exhibited an initially rapid, and gradually steadier release during 40 days, and the release rates could be tuned by its concentration. In vitro studies revealed that low concentrations of MMC could inhibit fibroblast adhesion and proliferation. When lacerate tendons were healed using the MMC-HA loaded PLLA fibers in vivo , they exhibited comparable mechanical strength to the naturally healed tendons but with no significant presence of adhesion formation. We further identified the up-regulation of apoptotic protein Bax expression and down-regulation of proteins Bcl2, collage I, collagen III and α-SMA during the healing process associated with minimum adhesion formations. This approach presented here leverages new advances in drug delivery and nanotechnology and offers a promising strategy to balance intrinsic and extrinsic tendon healing through modulating genes associated with fibroblast apoptosis and collagen synthesis. [ABSTRACT FROM AUTHOR]

Implantable tissue engineering scaffolds with temporally programmable multi-drug release are recognized as promising tools to improve therapeutic effects. A good example would be one that exhibits initial anti-inflammatory and long-term anti-tumor activities after tumor resection. In this study, a new strategy for self-coated interfacial layer on drug-loaded mesoporous silica nanoparticles (MSNs) based on mussel-mimetic catecholamine polymer (polydopamine, PDA) layer was developed between inorganic and organic matrix for controlling drug release. When the interface PDA coated MSNs were encapsulated in electrospun poly( l -lactide) (PLLA) fibers, the release rates of drugs located inside/outside the interfacial layer could be finely controlled, with short-term release of anti-inflammation ibuprofen (IBU) for 30 days in absence of interfacial interactions and sustained long-term release of doxorubicin (DOX) for 90 days in presence of interfacial interactions to inhibit potential tumor recurrence. The DOX@MSN-PDA/IBU/PLLA hybrid fibrous scaffolds were further found to inhibit proliferation of inflammatory macrophages and cancerous HeLa cells, while supporting the normal stromal fibroblast adhesion and proliferation at different release stages. These results have suggested that the interfacial obstruction layer at the organic/inorganic phase was able to control the release of drugs inside (slow)/outside (rapid) the interfacial layer in a programmable manner. We believe such interface polymer strategy will find applications in where temporally controlled multi-drug delivery is needed. [ABSTRACT FROM AUTHOR]

Peritendinous adhesions, as a major problem in hand surgery, may be due to the proliferation of fibroblasts and excessive collagen synthesis, in which ERK1/2 and SMAD2/3 plays crucial roles. In this study, we hypothesized that the complication progression could be inhibited by down-regulating ERK1/2 and SMAD2/3 phosphorylation of exogenous fibroblasts with celecoxib. Celecoxib was incorporated in poly( l -lactic acid)-polyethylene glycol (PELA) diblock copolymer fibrous membranes via electrospinning. Results of an in vitro drug release study showed celecoxib-loaded membrane had excellent continuous drug release capability. It was found that celecoxib-loaded PELA membranes were not favorable for the rabbit fibroblast and tenocyte adhesion and proliferation. In a rabbit tendon repair model, we first identified ERK1/2 and SMAD2/3 phosphorylation as a critical driver of early adhesion formation progression. Celecoxib released from PELA membrane was found to down-regulate ERK1/2 and SMAD2/3 phosphorylation, leading to reduced collagen I and collagen Ⅲ expression, inflammation reaction, and fibroblast proliferation. Importantly, the celecoxib-loaded PELA membranes successfully prevented tissue adhesion compared with control treatment and unloaded membranes treatment. This approach offers a novel barrier strategy to block tendon adhesion through targeted down-regulating of ERK1/2 and SMAD2/3 phosphorylation directly within peritendinous adhesion tissue. [ABSTRACT FROM AUTHOR]

Abstract: Prevention of hypertrophic scar formation of the skin requires a complex treatment process, which mainly includes promoting skin regeneration in an early stage while inhibiting hypertrophic formation in a later stage. Electrospinning PLGA with the three-dimensional micro/nano-fibrous structure and as drugs carrier, could be used as an excellent skin repair scaffold. However, it is difficult to combine the advantage of nanofibrous membranes and drug carriers to achieve early and late treatment. In this study, Ginsenoside-Rg3 (Rg3) loaded hydrophilic poly(d,l-lactide-co-glycolide) (PLGA) electrospun fibrous membranes coated with chitosan (CS) were fabricated by combining electrospinning and pressure-driven permeation (PDP) technology. The PDP method was able to significantly improve the hydrophilicity of electrospun fibrous membranes through surface coating of the hydrophilic fibers with CS, while maintaining the Rg3 releasing rate of PLGA electrospun fibrous membranes. Experimental wounds of animal covered with PDP treated fibrous membranes completely re-epithelialized and healed 3–4 days earlier than the wounds in control groups. Scar elevation index (SEI) measurements and histologic characteristics revealed that Rg3 significantly inhibited scar formation 28 days post-surgery. Moreover, RT-PCR assays and western blot analysis revealed that at day 28 after wound induction the expression of VEGF, mRNA and Collagen Type I in the scars treated with Rg3 was decreased compared to control groups. Taken together PLGA-Rg3/CS electrospun fibrous membranes induced repair of tissue damage in the early stage and inhibited scar formation in the late stage of wound healing. These dual-functional membranes present a combined therapeutic approach for inhibiting hypertrophic scars of the skin. [Copyright &y& Elsevier]

Abstract: Polymeric nanofibrous composite scaffolds incorporating bioglass and bioceramics have been increasingly promising for bone tissue engineering. In the present study, electrospun poly (l-lactic acid) (PLLA) scaffolds containing dicalcium silicate (C2S) nanoparticles (approximately 300nm) were fabricated. Using a novel ultrasonic dispersion and aging method, uniform C2S nanoparticles were prepared and they were homogenously distributed in the PLLA nanofibers upon electrospinning. In vitro, the PLLA-C2S fibers induced the formation of HAp on the surface when immersed in simulated body fluid (SBF). During culture, the osteoblastic MC3T3-E1 cells adhered well on PLLA-C2S scaffolds, as evidenced by the well-defined actin stress fibers and well-spreading morphology. Further, compared to pure PLLA scaffolds without C2S, PLLA-C2S scaffolds markedly promoted the proliferation of MC3T3-E1 cells as well as their osteogenic differentiation, which was characterized by the enhanced alkaline phosphatase (ALP) activity. Together, findings from this study clearly demonstrated that PLLA-C2S composite scaffold may function as an ideal candidate for bone tissue engineering. [Copyright &y& Elsevier]

Abstract: The ideal scaffolds should contain growth factors and thus can regulate cellular behaviors and tissue assembly. Electrospun fibrous membranes are widely-used scaffolds but growth factors are highly susceptible to losing their bioactivity during the electrospinning process. In this study, pre-formulated dextran glassy nanoparticles (DGNs) loaded with basic fibroblast growth factor (bFGF) were electrospun into a poly-l-lactic acid (PLLA) copolymer fiber to secure the bioactivity of bFGF in a sustained manner and then bioactivity retention was certificated by promoting cell proliferation and tendon healing. Meanwhile, the barrier effect of electrospun membrane was evaluated for clinic concern. In the in vitro release study, the protein encapsulation efficiency of the bFGF/DGNs-PLLA membrane reached 48.71 ± 13.53%, with a release kinetic of nearly 30 days. The enhanced cell proliferation and intrinsic tendon healing show that the bFGF/DGNs-loaded PLLA fibrous membrane can release bFGF sustainably and secure the bioactivity of bFGF better than the emulsion electrospun bFGF-loaded PLLA and PLLA fibrous membranes. Meanwhile, the anti-adhesion effect of electrospun membrane as barrier was fortunately combined as clinic concern. [Copyright &y& Elsevier]

Abstract: The complications of tendon injury are frequently compromised by peritendinous adhesions and tendon sheath infection. Physical barriers for anti-adhesion may increase the incidence of postoperative infection. This study was designed to evaluate the potential of silver nanoparticles (AgNPs)-loaded poly(l-lactide) (PLLA) electrospun fibrous membranes to prevent adhesion formation and infection. Results of an in vitro drug release study showed that a burst release was followed by sustained release from electrospun fibrous membranes with a high initial silver content. Fewer fibroblasts adhered to and proliferated on the AgNP-loaded PLLA electrospun fibrous membranes compared with pure PLLA electrospun fibrous membrane. In the antibacterial test, the AgNP-loaded PLLA electrospun fibrous membranes can prevent the adhesion of Gram-positive Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative Pseudomonas aeruginosa. Taken together, these results demonstrate that AgNP-loaded PLLA electrospun fibrous membranes have the convenient practical medical potential of reduction of infection and adhesion formation after tendon injury. [Copyright &y& Elsevier]

The hierarchical architecture and complex biologic functionsofnative sheath make its biomimetic substitute a daunting challenge.In this study, a biomimetic bilayer sheath membrane consisting ofhyaluronic acid–loaded poly(ε-caprolactone) (HA/PCL)fibrous membrane as the inner layer and PCL fibrous membrane as theouter layer was fabricated by a combination of sequential and microgelelectrospinning technologies. This material was characterized by mechanicaltesting and analysis of morphology, surface wettability, and drugrelease. Results of an in vitro drug release study showed sustainedrelease. The outer layer had fewer cells proliferating on its surfacecompared to tissue culture plates or the inner layer. In a chickenmodel, peritendinous adhesions were reduced and tendon gliding wereimproved by the application of this sheath membrane. Taken together,our results demonstrate that such a biomimetic bilayer sheath canrelease HA sustainably as well as promoting tendon gliding and preventingadhesion. [ABSTRACT FROM AUTHOR]

Abstract: It is essential to individually tailor the biodegradability of electrospun fibers and their composites to meet the requirements of specific application. Electrospun poly(dl-lactide) (PDLLA) fibers grafted with functional groups were obtained to induce in situ mineralization of hydroxyapatite (HA), and HA/PDLLA composites were fabricated through hot-pressing of mineralized fibers after layer-by-layer deposition. The degradation behaviors during up to 1 year incubation were clarified for functionalized PDLLA fibers, mineralized HA/PDLLA fibers and hot-pressed composites. The carboxyl and amino groups of electrospun fibers indicated enhancement and alleviation of the autocatalysis effect on the polyester hydrolysis, respectively. The distribution of HA within fiber matrices led quick and strong water absorption, and caused neutralization of the weak acid environment and alleviation of the autocatalysis effect. Due to the location of mineralized HA on the surface of functionalized fibers, significant HA loss and preferential removal of amorphous and low-crystalline apatitic phase were determined during the degradation process. The hot-pressed composites indicated dense structure, small pore size and fusion on the fiber surface, leading significantly lower degradation rate than electrospun fibers and mineralized fibers. Higher degradation rate of matrix polymers and HA loss were shown for hot-pressed composites from mineralized fibers than those from blend electrospun HA/PDLLA fibers. The obtained results should provide solid basis for further applications of functionalized PDLLA fibers, mineralized fibers and fibrous composites in biomedical areas. [Copyright &y& Elsevier]

Abstract: Hydroxycamptothecin (HCPT) is valid to various malignant tumors, but its insoluble and unstable lactone ring in physiological environment have restricted the clinic application. This work was aimed to formulate HCPT-loaded poly(dl-lactic acid)–poly(ethylene glycol) (PELA) fibrous mats through blend electrospinning with 2-hydroxypropyl-β-cyclodextrin (HPCD) to modulate the drug release and matrix degradation, and to enhance the structural integrity and cytotoxicity of the released HCPT. The entire drug fraction retained its active lactone form within electrospun fibers, and that was maintained over 85% during incubation for over 1 month. A biphasic release pattern was determined for HCPT-loaded electrospun fibers, which can be modulated by the addition of HPCD. HPCD served as solubilizer to maintain a large concentration gradient for HCPT between saturation and diffusion, and liberated HPCD created microstructure of ultrafine fibers, leading a faster release profile in the second phase. In vitro cytotoxicity test showed over 7 times higher inhibitory activity against cancer cells for HCPT-loaded electrospun fibers than free drug during 72h incubation. Higher apoptosis rates and the arrest of the cell cycle during the S and G2/M phases were detected through flow cytometry analysis. It indicated therapeutic potentials of HCPT-loaded electrospun fibers as implantable anti-cancer agents for local chemotherapy. [Copyright &y& Elsevier]

Abstract: Blending electrospinning of cadmium sulfide (CdS) quantum dots (QD) with poly(ethylene oxide) (PEO) solution was employed to fabricate one-dimensional ultrafine fibers with an average diameter of 450nm. This study focused on systematic investigations into the role of the matrix polymer and the optimal electrospinning parameters for enhancing the photoluminescence properties of fibrous composites. CdS QDs showed a homogeneous distribution within the composite fibers, and fluorescence spectra showed that PEO successfully passivated the interface defects and quenched the visible emission of CdS QDs. The QDs concentration and electrospinning voltage were found to play important roles in enhancing the passivation effect of PEO and adjusting the photoluminescence intensity of the composite fibers. Furthermore, the addition of polyaniline enhanced the photoluminescence intensity of the electrospun fibers, and an electron–hole mechanism was proposed. [Copyright &y& Elsevier]

[Display omitted] • Tannic acid as the structural matrix crosslinked Gelatin. • Acoustic transmitted electrospun fibrous membrane as tympanic membrane. • Improve the sound response sensitivity and reduce the sound loss. • Strong mechanical properties and excellent cellular adhesion. Scaffold with good acoustic transmission effect, high mechanical strength and good biocompatibility is a challenge for tympanic membrane (TM) regeneration. A new strategy using Tannic acid (TA) as the structural matrix crosslinked with Gelatin methacryloyl (Gelma) hydrogel, a new type of GelMA-TA double-cross-linked hydrogel acoustic transmitted electrospun fibrous membrane with good acoustic effect, strong mechanical properties and excellent cellular adhesion was constructed, implanted in situ to promote the TM regeneration. TA interacts with GelMA electrospun fibrous membrane to form N–H ···O = C and O-H···O = C intermolecular hydrogen bonds. By adjusting TA concentration, the mechanical strength of the GelMA-TA can be adjusted to improve the sound response sensitivity and reduce the sound loss. GelMA-TA has good porosity and biocompatibility, enabling the cells to adhere, penetrate and grow uniformly. Histological analysis and CD31 immunohistochemical analysis showed that GelMA-TA not only shortened the healing period of TM, but also improved the healing rate, forming a three-layer structure similar to the natural TM. GelMA-TA's excellent acoustic character were also confirmed by in vitro acoustic tests and in vivo objective audiological results. The GelMA-TA acoustic transmitted electrospun fibrous membranes proves to be efficient and versatile in TM structure and the function regeneration. [ABSTRACT FROM AUTHOR]

Periosteum as an important component in the construct of bone is mainly responsible for providing nourishment and regulating osteogenic differentiation. When bone defect happens, the functionality of periosteum will also be influenced, furthermore, it will finally hamper the process of bone regeneration. However, fabrication of an artificial periosteum with the capabilities in accelerating angiogenesis and osteogenesis in the defect area is still a challenge for researchers. In this study, we fabricated an organic-inorganic hybrid biomimetic periosteum by electrospinning, which can induce mineralization in situ and control the ions release for long-term in local area. Further, this system exhibited potential capabilities in promoting in vitro, which means the potentiality in accelerating bone regeneration in vivo. Calcium phosphate nanoparticles (CaPs) were fabricated by emulsion method, then CaPs were further incorporated with gelatin-methacryloyl (GelMA) by electrospinning fibers to construct the hybrid hydrogel fibers. The fibers exhibited satisfactory morphology and mechanical properties, additionally, controlled ions release could be observed for over 10 days. Further, significant mineralization was proved on the surface of hybrid fibers after 7 days and 14 days' co-incubation with simulated body fluid (SBF). Then, favorable biocompatibility of the hybrid fibers was approved by co-cultured with MC3T3-E1 cells. Finally, the hybrid fibers exhibited potential capabilities in promoting angiogenesis and osteogenesis by co-culture with HUVECs and MC3T3-E1 cells. This biomimetic organic-inorganic hybrid hydrogel electrospinning periosteum provided a promising strategy to develop periosteum biomaterials with angiogenesis and osteogenesis capabilities. CaPs incorporated GelMA hydrogel electrospinning fibers constantly release ions in situ, then mineralization appears on the surface of the fibers, which can promote osteogenic differentiation and angiogenesis. Unlabelled Image • Electrospinning for fabricating organic-inorganic hybrid hydrogel fibers • Constantly ions release and mineralization on the surface of hydrogel fibers in situ • Capability in promoting osteogenic differentiation and angiogenesis [ABSTRACT FROM AUTHOR]