Xiumei Mo

Donghua University, Shanghai, Shanghai Shi, China

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Publications (75)254.22 Total impact

  • [Show abstract] [Hide abstract]
    ABSTRACT: Emulsion electrospinning is a convenient and promising method for incorporating proteins and drugs into nanofiber scaffolds. The aim of this study was to fabricate a nanofiber scaffold for anticoagulation and rapid endothelialization. For this purpose, we encapsulated heparin and vascular endothelial growth factor (VEGF) into the core of poly(l-lactic acid-co-ɛ-caprolactone) (P(LLA-CL)) core-shell nanofibers via emulsion electrospinning. The fiber morphology, core-shell structure and hydrophilicity of the nanofiber mats were analyzed by scanning electron microscopy, transmission electron microscopy and water contact angle. The blood compatibility was measured by hemolysis and anticoagulation testing. A CCK-8 assay was performed to study the promotion of endothelial progenitor cell (EPC) growth and was complemented by immunofluorescent staining and SEM. Our study demonstrates that heparin and VEGF can be incorporated into P(LLA-CL) nanofibers via emulsion. The released heparin performed well as an anticoagulant, and the released VEGF promoted EPC growth on the fiber scaffolds. These results imply that electrospun P(LLA-CL) nanofibers containing heparin and VEGF have great potential in the development of vascular grafts in cases where antithrombogenicity and accelerated endothelialization are desirable. Copyright © 2015 Elsevier B.V. All rights reserved.
    Colloids and surfaces B: Biointerfaces 02/2015; 128C. DOI:10.1016/j.colsurfb.2015.02.023 · 4.29 Impact Factor
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    ABSTRACT: Particular attention has been given to three-dimensional scaffolds for bone tissue regeneration. In this study, poly(l-lactic acid-co-ε-caprolactone) (P(LLA-CL) nanoyarn scaffold and poly(l-lactic acid-co-caprolactone)/silk fibroin (P(LLA-CL)/SF) nanoyarn scaffold were fabricated by a dynamic liquid support electrospinning system; and then the three-dimensional (3D) nanoyarn scaffolds were prepared by freeze-drying processes. The results indicated the average diameter of P(LLA-CL) and P(LLA-CL)/SF nanoyarns were 29.44 ± 3.47 μm and 11.59 ± 0.46 μm, respectively. The yarn in the nanoyarn scaffold was twisted by many nanofibers as evidenced by scanning electron microscope (SEM) result. These nanoyarn scaffolds were biomineralized by alternatively immersing the nanoyarn scaffolds into phosphoric acid and calcium ion solutions. After biomineralization, the existence of hydroxyapatite (HA) particles on the scaffolds was confirmed using fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD) analysis. In vitro study of cell proliferation was found to be higher on P(LLA-CL)/SF scaffold as compared to P(LLA-CL) scaffold after culturing for 14 days. H&E staining results showed that cells not only attached to the surface of 3D scaffold but also infiltrated into the scaffold. This study indicated that the electrospun P(LLA-CL)/SF scaffold with nanostructure morphology could improve cell adhesion and proliferation and electrospun P(LLA-CL)/SF scaffold with biomineralization has a potential application for bone tissue engineering.
    Iranian Polymer Journal 12/2014; 24(1). DOI:10.1007/s13726-014-0297-9 · 1.47 Impact Factor
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    ABSTRACT: While surface modification is well suited for imparting biomaterials with specific functionality for favorable cell interactions, the modification of degradable polymers would be expected to provide only temporary benefit. Bulk modification by incorporating pendant reactive groups for subsequent functionalization of biodegradable polymers would provide a more enduring approach. Towards this end, a series of biodegradable poly(ester urethane)urea elastomers with variable amino content (PEUU-NH2 polymers) were developed. Carboxylated phosphorycholine was synthesized and conjugated to the PEUU-NH2 polymers for subsequent bulk functionalization to generate PEUU-PC polymers. Synthesis was verified by proton nuclear magnetic resonance, X-ray photoelectron spectroscopy and attenuated total reflection Fourier transform infrared spectroscopy. The impact of amine incorporation and phosphorylcholine conjugation was shown on mechanical, thermal and degradation properties. Water absorption increased with increasing amine content, and further with PC conjugation. In wet conditions, tensile strength and initial modulus generally decreased with increasing hydrophilicity, but remained in the range of 5-30 MPa and 10-20 MPa, respectively. PC conjugation was associated with significantly reduced platelet adhesion in blood contact testing and the inhibition of rat vascular smooth muscle cell proliferation. These biodegradable PEUU-PC elastomers offer attractive properties for applications as non-thrombogenic, biodegradable coatings and for blood-contacting scaffold applications. Further, the PEUU-NH2 base polymers offer the potential to have multiple types of biofunctional groups conjugated onto the backbone to address a variety of design objectives.
    Acta Biomaterialia 11/2014; 10(11). DOI:10.1016/j.actbio.2014.08.008 · 5.68 Impact Factor
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    ABSTRACT: Silk fibroin (SF)/PEO nanofibers prepared by green electrospinning is safe, non-toxic and environment friendly, it is a potential drug delivery carrier for tissue engineering. In this study, a core-shell nanofibers named as Dex@SF/PEO were obtained by green electrospinning with SF/PEO as the shell and dexamethasone (Dex) in the core. The nanofiber morphology and core-shell structure were studied by Scanning Electron Microscope (SEM) and Transmission Electron Microscope (TEM). The Dex release behavior from the nanofibers was tested by High Performance liquid (HPLC) method. The protective effect of drug loaded nanofibers mats on Porcine hip artery endothelial cells (PIECs) against LPS-induced inflammatory damage were determined by MTT assay. TEM result showed the distinct core-shell structure of nanofibers. In vitro drug release studies demonstrated that dexamethasone can sustain release over 192h and core-shell nanofibers showed more slow release of Dex compared with the blending electrospinning nanofibers. Anti-inflammatory activity in vitro showed that released Dex can reduce the PIECs inflammatory damage and apoptosis which induced by lipopolysaccharide (LPS). Dex@SF/PEO nanofibers are safe and non-toxic because of no harmful organic solvents used in the preparation, it is a promising environment friendly drug carrier for tissue engineering. Copyright © 2014 Elsevier B.V. All rights reserved.
    Colloids and surfaces B: Biointerfaces 09/2014; 126. DOI:10.1016/j.colsurfb.2014.09.016 · 4.29 Impact Factor
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    ABSTRACT: In the vascular prosthetic field, the prevailing thought is that for clinical, long-term success, especially bioresorbable grafts, cellular migration and penetration into the prosthetic structure is required to promote neointima formation and vascular wall development. In this study, we fabricated poly (l-lactic acid-co-�-caprolactone) P(LLA-CL)/silk fibroin (SF) vascular scaffolds through electrospinning using both perforated mandrel subjected to various intraluminal air pressures (0–300 kPa), and solid mandrel. The scaffolds were evaluated the cellular infiltration in vitro and mechanical properties. Vascular scaffolds were seeded with smooth muscle cells (SMCs) to evaluate cellular infiltration at 1, 7, and 14 days. The results revealed that air-impedance scaffolds allowed significantly more cell infiltration as compared to the scaffolds fabricated with solid mandrel. Meanwhile, results showed that both mandrel model and applied air pressure determined the interfiber distance and the alignment of fibers in the enhanced porosity regions of the structure which influenced cell infiltration. Uniaxial tensile testing indicated that the air-impedance scaffolds have sufficient ultimate strength, suture retention strength, and burst pressure as well as compliance approximating a native artery. In conclusion, the air-impedance scaffolds improved cellular infiltration without compromising overall biomechanical properties. These results support the scaffold’s potential for vascular grafting and in situ regeneration.
    Colloids and surfaces B: Biointerfaces 08/2014; 120:47-54. · 4.29 Impact Factor
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    ABSTRACT: Background: Capping techniques have been used as a treatment modality for the prevention of neuroma formation and the management of neuropathic pain. However, the results are inconsistent and unpredictable. We hypothesize that this situation may be attributable, in part, to the disparities in the type of materials used to manufacturing of the conduits. Methods: In this study, a rat model was used and the sciatic nerve was selected for evaluation. In 1 capping group, a sciatic nerve stump was capped with a nonaligned nanofiber conduit (the nonaligned group), whereas in a second capping group, the conduit was made of aligned nanofibers (the aligned group). In another group, the sciatic nerve stump was not capped as a control (the control group). The results of autotomy behavior, extent of neuroma formation, histological changes in the neuroma, and the expression of c-fos as a pain marker in the fourth lumbar spinal cord were evaluated at 8 weeks postoperatively. Results: The control group presented more neuroma-like features in all the observed parameters in comparison with the 2 capping groups; of the 2 capping groups, the aligned group achieved even better outcomes than the nonaligned group. Conclusions: Our findings indicate that the aligned nanofiber conduit is a promising biomaterial for the nerve capping technique, and new treatment strategies using aligned nanofiber conduits may be developed for the management of painful amputated neuromas. Copyright
    Annals of Plastic Surgery 07/2014; DOI:10.1097/SAP.0000000000000266 · 1.46 Impact Factor
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    ABSTRACT: An electrospun-aligned nanoyarn-reinforced nanofibrous scaffold (NRS) was developed for tendon tissue engineering to improve mechanical strength and cell infiltration. The novel scaffold composed of aligned nanoyarns and random nanofibers was fabricated via electrospinning using a two-collector system. The aim of the present study was to investigate three different types of electrospun scaffolds (random nanofibrous scaffold, aligned nanofibrous scaffold and NRS) based on silk fibroin (SF) and poly(l-lactide-co-caprolactone) blends. Morphological analysis demonstrated that the NRS composed of aligned nanoyarns and randomly distributed nanofibers formed a 3D microstructure with relatively large pore sizes and high porosity. Biocompatibility analysis revealed that bone marrow-derived mesenchymal stem cells exhibited a higher proliferation rate when cultured on the NRS compared with the other scaffolds. The mechanical testing results indicated that the tensile properties of the NRS were reinforced in the direction parallel to the nanoyarns and satisfied the mechanical requirements for tendon repair. In addition, cell infiltration was significantly enhanced on the NRS. In conclusion, with its improved porosity and appropriate mechanical properties, the developed NRS shows promise for tendon tissue engineering applications.
    Colloids and surfaces B: Biointerfaces 07/2014; 122C:270-276. DOI:10.1016/j.colsurfb.2014.06.061 · 4.29 Impact Factor
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    ABSTRACT: Osteochondral defects affect both the articular cartilage and the underlying subchondral bone, but poor osteochondral regeneration is still a daunting challenge. Although the tissue engineering technology provides a promising approach for osteochondral repair, an ideal biphasic scaffold is in high demand with regards to proper biomechanical strength. In this study, an oriented poly( L -lacticacid)- co -poly( ε -caprolactone) P(LLA-CL)/collagen type I(Col-I) nanofiber yarn mesh, fabricated by dynamic liquid electrospinning served as a skeleton for a freeze-dried Col-I/ Hhyaluronate (HA) chondral phase(SPONGE) to enhance the mechanical strength of the scaffold. In vitro results show that the Yarn Col-I/HA hybrid scaffold (Yarn-CH) can allow the cell infiltration like sponge scaffolds. Using porous beta-tricalcium phosphate (TCP) as the osseous phase, the Yarn-CH/TCP biphasic scaffold was then assembled by freeze drying. After combination of BMSCs, the biphasic complex was successfully used to repair the osteochondral defects in a rabbit model with greatly improved repairing scores and compressive modulus.
    Journal of Biomedical Materials Research Part A 07/2014; DOI:10.1002/jbm.a.35206 · 2.83 Impact Factor
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    ABSTRACT: This paper presents a facile method for the fabrication of uniform hollow mesoporous silica nanoparticles (HMSNs) with tunable shell thickness and pore size. In this method, a series of amphiphilic block copolymers of polystyrene-b-poly (acrylic acid) (PS-b-PAA) with different hydrophobic block (PS) lengths were first synthesized via atom transfer radical polymerization (ATRP). The as-synthesized PS-b-PAA and cetyltrimethylammonium bromide (CTAB) were subsequently used as co-templates to fabricate HMSNs. This approach allows the control of shell thickness and pore size distribution of the synthesized HMSNs simply by changing the amounts of PS-b-PAA and CTAB, respectively. In vitro cytotoxicity and hemolysis assays demonstrated that the synthesized HMSNs had a low and shell thickness-dependent cytotoxicity and hemolytic activity. Therefore, these HMSNs have great potential for biomedical applications due to their good biocompatibility and ease of synthesis.
    Dalton Transactions 06/2014; 43(31). DOI:10.1039/c4dt01138d · 4.10 Impact Factor
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    ABSTRACT: Electrospinning has been widely used in fabrication of tissue engineering scaffolds. Currently, most of the electrospun nanofibers performed like a conventional two-dimensional (2D) membrane, which hindered their further applications. Moreover, the low production rate of the traditional needle-electrospinning (NE) also limited the commercialization. In this article, disc-electrospinning (DE) was utilized to fabricate a three-dimensional (3D) scaffold consisting of porous macro/nanoscale fibers. The morphology of the porous structure was investigated by scanning electron microscopy images, which showed irregular pores of nanoscale spreading on the surface of DE polycaprolactone (PCL) fibers. Protein adsorption assessment illustrated the porous structure could significantly enhance proteins pickup, which was 55% higher than that of solid fiber scaffolds. Fibroblasts were cultured on the scaffold. The results demonstrated that DE fiber scaffold could enhance initial cell attachment. In the 7 days of culture, fibroblasts grew faster on DE fiber scaffold in comparison with solid fiber, solvent cast (SC) film and TCP. Fibroblasts on DE fibers showed a stretched shape and integrated with the porous surface tightly. Cells were also found to migrate into the DE scaffold up to 800μm. Results supported the use of DE PCL fibers as a 3D tissue engineering scaffold in soft tissue regeneration.
    Colloids and surfaces B: Biointerfaces 06/2014; 121. DOI:10.1016/j.colsurfb.2014.06.034 · 4.29 Impact Factor
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    ABSTRACT: Poly(l-lactic acid-co-ε-caprolactone) (P(LLA-CL)) is a kind of copolymer polymerized from lactic acid and ε-caprolactone. Electrospun P(LLA-CL) nanofibers have good biocompatibility, biodegradability, and mechanical property. However, this type of nanofibers will produce acid groups during the degradation, so that, the pH value of the environment will decrease and result in tissue inflammation. On the other hand, Magnesium (Mg) alloy tissue engineering scaffolds will show alkaline during the degradation because of the electrochemical corrosion. Based on the principle of acid-based neutralization, combination of these two kinds of materials through electrospinning could keep the pH of the degradation environment neutral. In this paper, fabrication and characterization of Mg/P(LLA-CL)-blended nanofiber scaffolds with different ratios will be studied by scanning electron microscopy and universal materials testing machines to observe the morphology and mechanical properties of nanofibers, respectively. Furthermore, PIECs were cultured and seeded on the scaffolds for different time to evaluate the proliferation behavior on the scaffolds by MTT assay. The degradation tests of the samples lasted for three months in phosphate-buffered saline to evaluate the pH values of degradation solutions and the weight loss of nanofibers during degradation. The results showed that the mechanical property and biocompatibility of Mg/P(LLA-CL)-blended nanofibers were worse than that of pure P(LLA-CL). Moreover, the addition of Mg in the nanofibers accelerated the weight loss of the Mg/P(LLA-CL) blending fibers and increased the pH values of the environment during degradation of Mg/P(LLA-CL)-blended nanofibers.
    Journal of Biomaterials Science Polymer Edition 06/2014; DOI:10.1080/09205063.2014.918456 · 1.36 Impact Factor
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    ABSTRACT: In the vascular prosthetic field, the prevailing thought is that for clinical, long-term success, especially bioresorbable grafts, cellular migration and penetration into the prosthetic structure is required to promote neointima formation and vascular wall development. In this study, we fabricated poly (l-lactic acid-co-ɛ-caprolactone) P(LLA-CL)/silk fibroin (SF) vascular scaffolds through electrospinning using both perforated mandrel subjected to various intraluminal air pressures (0-300kPa), and solid mandrel. The scaffolds were evaluated the cellular infiltration in vitro and mechanical properties. Vascular scaffolds were seeded with smooth muscle cells (SMCs) to evaluate cellular infiltration at 1, 7, and 14 days. The results revealed that air-impedance scaffolds allowed significantly more cell infiltration as compared to the scaffolds fabricated with solid mandrel. Meanwhile, results showed that both mandrel model and applied air pressure determined the interfiber distance and the alignment of fibers in the enhanced porosity regions of the structure which influenced cell infiltration. Uniaxial tensile testing indicated that the air-impedance scaffolds have sufficient ultimate strength, suture retention strength, and burst pressure as well as compliance approximating a native artery. In conclusion, the air-impedance scaffolds improved cellular infiltration without compromising overall biomechanical properties. These results support the scaffold's potential for vascular grafting and in situ regeneration.
    Colloids and surfaces B: Biointerfaces 05/2014; 120C:47-54. DOI:10.1016/j.colsurfb.2014.04.011 · 4.29 Impact Factor
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    ABSTRACT: Silk fibroin (SF) from Bombyx mori has many established excellent properties and has found various applications in the biomedical field. However, some abilities or capacities of SF still need improving to meet the need for using practically. Indeed, diverse SF-based composite biomaterials have been developed. Here we report the feasibility of fabricating pantothenic acid (vitamin B5, VB5)-reinforcing SF nanofibrous matrices for biomedical applications through green electrospinning. Results demonstrated the successful loading of d-pantothenic acid hemicalcium salt (VB5-hs) into resulting composite nanofibers. The introduction of VB5-hs did not alter the smooth ribbon-like morphology and the silk I structure of SF, but significantly decreased the mean width of SF fibers. SF conformation transformed into β-sheet from random coil when composite nanofibrous matrices were exposed to 75% (v/v) ethanol vapor. Furthermore, nanofibers still remained good morphology after being soaked in water environment for five days. Interestingly, as-prepared composite nanofibrous matrices supported a higher level of cell viability, especially in a long culture period and significantly assisted skin cells to survive under oxidative stress compared with pure SF nanofibrous matrices. These findings provide a basis for further extending the application of SF in the biomedical field, especially in the personal skin-care field.
    Colloids and surfaces B: Biointerfaces 05/2014; 117:14–20. DOI:10.1016/j.colsurfb.2013.12.030 · 4.29 Impact Factor
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    ABSTRACT: A novel electrospun nanoyarn scaffold, aimed to improve cell infiltration and vascularization, as well as guide cell behaviors by its biomimetic structure, was fabricated for tissue engineering. Electrospun nanofibers were deposited and twisted into yarns in a water vortex before collecting on a rotating mandrel to form a nanoyarn scaffold. Field emission-scanning electronic microscope (FE-SEM) images revealed that the scaffold, composed of aligned nanoyarns (24 micro m) which were composed of a bundle of nanofibers, created a porous structure which may be conducive to cellular infiltration. Thus, we hypothesized that the biomimetic nanoyarn will have a positive influence on cell proliferation and morphology. Pig iliac endothelial cells (PIECs) and MC3T3-E1 pre-osteoblastic cells cultured on the nanoyarn scaffolds showed significantly higher proliferation rates than that on traditional electrospun nanofiber scaffolds. Histological analysis demonstrated that cells infiltrate throughout the nanoyarn scaffolds over a 10-day period, however, no cell infiltration was observed on the nanofiber scaffolds. Moreover, confocal microscopy images indicated that both PIECs and MC3T3-E1 pre-osteoblastic cells cultured on the nanoyarn scaffolds exhibit an extremely elongated morphology compared to the flattened morphology when cells were cultured on electrospun nanofiber scaffolds or tissue culture plates. Furthermore, complex capillary-like structures were observed when PIECs cultured on the nanoyarn scaffold for 7 days, indicating that the nanoyarns provide templates and topographical cues for the assembly of PIECs and the promotion of a capillary network in vitro. In conclusion, the positive cellular interactions on the nanoyarn scaffold demonstrate potential application for use in tissue engineering.
    Journal of Biomedical Nanotechnology 04/2014; 10(4):603-14. DOI:10.1166/jbn.2014.1733 · 7.58 Impact Factor
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    ABSTRACT: The metallic stents covered with heparin loaded poly(l-lactide-co-caprolactone) nanofibers via emulsion electrospinning have been fabricated as a novel covered stent. The morphology and inner-structure of core–shell nanofibers were respectively ion observed by scanning electron microscopy and transmission electron microscopy. The distribution of heparin aqueous solution and chemical component in nanofibers was separately determined by fluorescence microscopy and Fourier transform infrared spectrum. The results showed that the nanofibrous matrix successfully encapsulated with heparin would not rupture with the expansion of metallic stent, which could effectively separate the aneurysm dome with bloodstream in the rabbit model. The aneurysm was immediately obliterated after the stenting and angiogram at 14 days follow-up showed that the aneurysm was still obliterated. No obvious stenosis and intima hyperplasia in parent artery were found. Therefore, this work provides a promising approach to fabricate covered stent for aneurysm treatment.
    Materials Letters 02/2014; 116:39–42. DOI:10.1016/j.matlet.2013.10.018 · 2.27 Impact Factor
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    ABSTRACT: Mechanical stimulation plays an important role in the development and remodeling of tendons. Tendon-derived stem cells (TDSCs) are an attractive cell source for tendon injury and tendon tissue engineering. However, these cells have not yet been fully explored for tendon tissue engineering application, and there is also lack of understanding to the effect of mechanical stimulation on the maturation of TDSCs-scaffold construct for tendon tissue engineering. In this study, we assessed the efficacy of TDSCs in a poly(L-lactide-co-ε-caprolactone)/collagen (P(LLA-CL)/Col) scaffold under mechanical stimulation for tendon tissue engineering both in vitro and in vivo, and evaluated the utility of the transplanted TDSCs-scaffold construct to promote rabbit patellar tendon defect regeneration. TDSCs displayed good proliferation and positive expressed tendon-related extracellular matrix (ECM) genes and proteins under mechanical stimulation in vitro. After implanting into the nude mice, the fluorescence imaging indicated that TDSCs had long-term survival, and the macroscopic evaluation, histology and immunohistochemistry examinations showed high-quality neo-tendon formation under mechanical stimulation in vivo. Furthermore, the histology, immunohistochemistry, collagen content assay and biomechanical testing data indicated that dynamically cultured TDSCs-scaffold construct could significantly contributed to tendon regeneration in a rabbit patellar tendon window defect model. TDSCs have significant potential to be used as seeded cells in the development of tissue-engineered tendons, which can be successfully fabricated through seeding of TDSCs in a P(LLA-CL)/Col scaffold followed by mechanical stimulation.
    Biomaterials 01/2014; DOI:10.1016/j.biomaterials.2013.12.042 · 8.31 Impact Factor
  • Journal of Controlled Release 11/2013; 172(1):e130. DOI:10.1016/j.jconrel.2013.08.208 · 7.26 Impact Factor
  • Xiaohua Geng, Xiumei Mo
    Journal of Controlled Release 11/2013; 172(1):e143-4. DOI:10.1016/j.jconrel.2013.08.233 · 7.26 Impact Factor
  • Journal of Controlled Release 11/2013; 172(1):e144-5. DOI:10.1016/j.jconrel.2013.08.235 · 7.26 Impact Factor
  • Journal of Controlled Release 11/2013; 172(1):e141. DOI:10.1016/j.jconrel.2013.08.228 · 7.26 Impact Factor

Publication Stats

858 Citations
254.22 Total Impact Points

Institutions

  • 2006–2015
    • Donghua University
      • • College of Chemistry, Chemical Engineering & Biotechnology
      • • State Key Laboratory for Modification of Chemical Fibers and Polymer Materials
      • • Key Laboratory of Textile Technology
      • • College of Materials Science and Engineering
      • • Institute of Biological Sciences and Biotechnology
      Shanghai, Shanghai Shi, China
  • 2011–2014
    • King Saud University
      • Department of Chemistry
      Ar Riyāḑ, Ar Riyāḑ, Saudi Arabia
  • 2000
    • Kyoto University
      • Institute for Frontier Medical Sciences
      Kioto, Kyōto, Japan