INTERNATIONAL JOURNAL OF HYDROGEN ENERGY
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2019
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IF 4.084
Jie Wang,Chunli Gong,Sheng Wen,Hai Liu,Caiqin Qin,Chuanxi Xiong,Lijie Dong
Recently, fabricating low-cost and high-performance proton exchange membranes (PEMs) with carbon nanotubes (CNTs) and chitosan (CS) have been extensively studied. Herein, we reported a facile but effective method to prepare CS-based PEM with polydopamine (PDA) functionalized CNTs (PDA@CNTs). The CS/PDA@CNTs composite membranes were prepared by incorporating PDA@CNTs into CS matrix followed by ion cross-linking with sulfuric acid. Due to the hydrogen bonding between the CS matrix and PDA coating, the thermal, mechanical and oxidation stability of the CS/PDA@CNTs composite membranes were improved. Moreover, the proton conductivity was also improved owing to the improved dispersion of PDA@CNTs in the CS matrix and the electrostatic interaction between PDA@CNTs and CS matrix. The maximum proton conductivity can reach to as high as 0.028 S cm −1 under 80 °C with 2 wt% loading of PDA@CNTs. These results indicate that the CS/PDA@CNTs composite membranes have great potential to be used as PEMs in fuel cells.
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Jing Miao,Xi-qin Yang,Zhe Gao,Qian Li,Ting-ting Meng,Jia-ying Wu,Hong Yuan,Fu-qiang Hu
DrzBC and DrzBS (10-23 DNAzyme) could block the expression of HBV e- and s- gene respectively. But the application of 10-23 DNAzyme was limited owing to the lack of appropriate delivery vehicles. Chitosan oligosaccharide-SS-Octadecylamine (CSSO), a redox-responsive nano-sized polymeric carrier, could self-aggregate and bind with DNA by electrostatic interaction at proper mass ratio. Compared with the traditional commercial carrier Lipo2000, CSSO exhibited lower cytotoxicity, efficient cellular uptake by targeting cells, and rapidly DNA released in cytoplasm after escaping from endosomes. Including the same DNA concentration, Lipo2000/(DrzBC or DrzBS) showed maximum inhibitory rate on HBeAg (47.29 ± 1.86%) and HBsAg (33.58 ± 0.72%) secretion after 48 h incubation, and then both decreased. In contrast, HBeAg secretion inhibition by CSSO/DrzBC and HBsAg secretion inhibition by CSSO/DrzBS were up to 73.86 ± 1.77% and 67.80 ± 2.51% at 48 h, and further increased to 83.83 ± 2.34% and 76.79 ± 2.18% at 72 h, respectively. CSSO is a promising redox-responsive polymeric carrier for efficient anti-Hepatitis B Virus gene therapy.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Xianzhen Yin,Yiting Li,Congling Yang,Jie Weng,Jianxin Wang,Jie Zhou,Bo Feng
Macrophage phenotype conversion is crucial for improving post-traumatic angiogenesis and tissue repair. Biomaterials with the ability of skewing macrophage phenotype have attracted widespread attention in the field of tissue engineering. The aim of this study was to transform macrophage phenotype by a three-step process; anodizing, drug loading and coating with polyelectrolyte multilayer (PEM) films. Interleukin (IL)-4, an anti-inflammatory cytokine, was loaded into titania nanotubes (TNTs) on the titanium surface. Subsequently, sodium alginate (ALG) and chitosan (CS) were alternately assembled onto IL-4-loaded TNTs and cross-linked with genipin/calcium chloride, finally forming cross-linked PEM films. The IL-4 release profile and cellular immune response of the modified surface was investigated. In the simulated biological solution, only 20% of IL-4 were detected in the first 3 days, with a sustained release of approximately 5 ng over 10 days. The results of gene expression and protein secretion in macrophages indicated that IL-4-loaded PEM films significantly attenuated the inflammatory activity of macrophages at the later stage through down-regulating the mRNA and protein levels of inflammatory markers. In summary, IL-4 was controlled released from the cross-linked PEM films deposited on the nanotubes, leading to the temporal conversion of macrophage phenotype.
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DRUG DEVELOPMENT AND INDUSTRIAL PHARMACY
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2019
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IF 2.367
Jing Zhou,Yuanyuan Chen,Mengmeng Luo,Fen Deng,Sen Lin,Wencan Wu,Guqiang Li,Kaihui Nan
Objective: This study was aimed to develop sustained drug release from levofloxacin (LF)-loaded chitosan (CS) microspheres for treating ophthalmic infections.Significance: Dual cross-linked CS microspheres developed by the spray-drying technique displays significantly higher level of sustained drug release compared with non-cross-linked CS microspheres.Methods: LF-loaded CS microspheres were prepared using the spray-drying technique, and then solidified with tripolyphosphate and glutaraldehyde as dual cross-linking agents. The microspheres were characterized by surface morphology, size distribution, zeta potential, encapsulation efficiency, and drug release profiles in vitro. The drug quantification was verified and analyzed by high-performance liquid chromatography (HPLC). The structural interactions of the CS with LF were studied with Fourier transform infrared spectroscopy. The effect of various influencing excipients in the formulation of the dual cross-linked CS microspheres on drug encapsulation efficiency and the drug release profiles were extensively investigated.Result: The microspheres demonstrated high encapsulation efficiency (72.4 ∼ 98.55%) and were uniformly spherical with wrinkled surface. The mean particle size was between 1020.7 ± 101.9 and 2381.2 ± 101.6 nm. All microspheres were positively charged (zeta potential ranged from 31.1 ± 1.32 to 42.81 ± 1.55 mV). The in vitro release profiles showed a sustained release of the drug and it was remarkably influenced by the cross-linking process.Conclusion: This novel spray-drying technique we have developed is suitable for manufacturing LF-loaded CS microspheres, and thus could serve as a potential platform for sustained drug release for effective therapeutic application in ocular infections.
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Journal of Materials Chemistry B
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2019
·Vol. 7
·期 11
·1882-1892
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IF 5.047
Chenmin Wang,Yuanman Yu,Han Chen,Shuang Zhang,Jing Wang,Changsheng Liu
Nutrients and oxygen are delivered mainly by blood vessels to nourish the cells and tissues in the body. Thus, biomaterials are processed by loading cytokines, such as vascular endothelial growth factors (VEGF), to facilitate angiogenesis in order to accelerate tissue regeneration. Nevertheless, the unpredictable biosecurity of exogenous cytokines is still a controversial issue for its clinical application. In this study, we constructed a kind of cytokine reservoir utilizing the binding affinity between heparin-like sulfate polysaccharide and endogenous growth factors. Two types of sulfated chitosan hydrogels, namely 6-O-sulfated chitosan (6-O-SCS) and 2-N,6-O-sulfated chitosan (2-N,6-O-SCS) hydrogels, were formed on the surface of the gelatin sponge matrix. The microstructure of the SCS-coated scaffolds is porous and interconnected, which is beneficial for cellular infiltration. Besides, human umbilical vein endothelial cells (HUVECs) can adhere and proliferate well on the surface of the scaffolds. Notably, sulfated chitosan-coated scaffolds exhibit an ability to capture VEGF in vitro & vivo, especially for the 2-N,6-O-SCS-coated scaffold. It is also verified by mice models that sulfated chitosan-coated scaffolds result in a concentrated VEGF microenvironment in specific domains as cytokine reservoirs and induce mass microvessels after implantation into subcutaneous tissues. As such, the sulfated chitosan-coated scaffolds served as VEGF reservoirs to accelerate angiogenesis and wound healing. This beneficial strategy may be applicable to in situ tissue regeneration by capturing more cytokines and promoting healing.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Xiaoxiao Sun,Chao Liu,A.M. Omer,Wuhuan Lu,Shuxing Zhang,Xun Jiang,Hongjie Wu,Di Yu,Xiao-kun Ouyang
To develop relatively green and ecofriendly smart vehicles for colon-specific drug delivery, carboxymethyl cellulose (CMC) and chitosan (CS) pH-sensitive biopolymers were used in this study. To overcome the weaknesses of CMC carriers, such as poor mechanical performance and an explosive drug release, zinc oxide (ZnO) nanoparticles were incorporated into CMC beads and then coated with a CS layer via a self-assembly technique to form core–shell polyelectrolyte complexes. An anticancer drug, 5-fluorouracil (5-FU), used as a model drug, was loaded into ZnO/CMC/CS bio-nanocomposite beads. Fourier transform infrared spectroscopy , scanning and transmission electron microscopy , and thermogravimetric analysis were used to characterize the chemical structure, morphological changes, and thermal properties of the developed drug carrier, respectively. By studying their swelling and in vitro 5-FU release profiles under simulated gastrointestinal conditions, the pH sensitivity of the developed bio-nanocomposite hydrogel beads could be investigated. The obtained beads with reduced porosity could effectively encapsulate 5-FU and showed self-sustained release behavior depending on the concentrations of CMC, CS, and ZnO nanoparticles. The developed beads also demonstrated a capacity for biodegradation. The results indicated that the ZnO/CMC/CS bio-nanocomposite beads exhibited pH-sensitivity and could be applied efficiently as biodegradable carriers for colon-specific 5-FU delivery.
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JOURNAL OF HAZARDOUS MATERIALS
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2019
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IF 7.65
Yuanfeng Wei,Xingwen Yu,Chengbin Liu,Jianhong Ma,Shudan Wei,Tao Chen,Kai Yin,Hui Liu,Shenglian Luo
Although Fe-chitosan adsorbents are attractive for removing arsenite from water, the practical applications of these granular adsorbents are mainly limited by slow adsorption kinetics. In this study, radially porous Fe-chitosan beads (P/Fe-CB) were prepared using freeze-casting technique. The P/Fe-CB particles possess radially aligned micron-sized tunnels from the surface to the inside as well as excellent acid resistance. Kinetic studies show that the adsorption equilibrium time of P/Fe-CB to 0.975 mg/L As(III) (within 240 min) is considerably shorter than that of compact Fe-chitosan beads (over 600 min). The maximal adsorption capacity of P/Fe-CB for As(III) is 52.7 mg/g. It can work effectively in a wide pH range from 3 to 9, and the coexisting sulfate, carbonate, silicate and humic acid have no significant effect on As(III) removal. The addition of H 2 O 2 can further accelerate and promote the As(III) removal except at high pH (11) and phosphate concentration (50 mg/L). The fixed-bed experiments demonstrate that the P/Fe-CB column can effectively treat about 3000 bed volume (BV) of simulated As(III)-containing groundwater to meet the drinking water standard (<10 μg As/L). This study would extend the potential applicability of porous Fe based chitosan adsorbent and millimeter-sized adsorbent combined with H 2 O 2 to a great extent.
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Experimental and Therapeutic Medicine
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2019
·Vol. 17
·期 5
·3891-3898
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IF 1.448
Yuan‑Jun Xia,Wang Wei,Hong Xia,Qing‑Shui Ying,Xiang Yu,Li‑Hua Li,Jian‑Hua Wang,Ying Zhang
In the present study, the effect of recombinant human bone morphogenetic protein‑2 (rhBMP‑2) delivered by chitosan (CS) microspheres on ectopic osteogenesis was investigated in a rat model. rhBMP‑2‑loaded CS microspheres and blank CS microspheres were prepared. A total of 24 male Sprague Dawley rats were divided into 4 groups with 6 rats in each group: The CS/rhBMP‑2 group, the rhBMP‑2 group, in which rhBMP‑2 was directly implanted (rhBMP‑2 dose in either group, 1 mg), the CS blank group and the control group. X‑ray was performed at 4 weeks after ectopic osteogenesis surgery and micro‑computed tomography (CT) examination was scheduled at 1, 2, 3 and 4 weeks after the surgery to determine ectopic osteogenesis in the different groups. Histological analysis, and determination of alkaline phosphatase (ALP) activity and calcium content were also performed. The mean diameter of the osteoid tissues was 1.1±0.3 cm (range, 0.8‑1.4 cm) in the CS/rhBMP‑2 group, which was significantly bigger than that in the rhBMP‑2 group (0.3±0.1 cm; range, 0.1‑0.4 cm) at 4 weeks after the surgery. X‑ray analysis and micro‑CT scan indicated that the area of high‑density tissues and the radionuclide intensity, as well as bone volume in the 3‑dimensional reconstruction were greatest in the CS/rhBMP‑2 group, followed by those in the rhBMP‑2 group. All parameters, including bone mineral density, tissue mineral density, tissue mineral content and bone volume fraction, were significantly higher in the CS/rhBMP‑2 group at 3 and 4 weeks after the surgery, compared with those in the rhBMP‑2 group. The histological analysis, ALP activity analysis and determination of calcium content revealed that the CS/rhBMP‑2 system had the greatest ability to induce osteoblast differentiation. In conclusion, the CS/rhBMP‑2 microsphere delivery system significantly enhanced the induction and promotion effects of rhBMP‑2 regarding ectopic osteogenesis. The present study enhances the basic data available for future application of the CS/rhBMP‑2 microspheres delivery system and provides a deeper understanding of the role of BMP‑2 in bone regeneration.
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SCIENCE OF THE TOTAL ENVIRONMENT
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2019
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IF 5.589
Aijiao Zhou,Wangwei Chen,Lei Liao,Pengchao Xie,Tian C. Zhang,Xumeng Wu,Xiaonan Feng
The magnetic poly( N -isopropylacrylamide)/chitosan hydrogel with interpenetrating network (IPN) structure was designed based on the functional groups of targeted emerging contaminants , represented by hydrophilic sulfamethoxazole (SMZ) and hydrophobic bisphenol A (BPA). The average particle size, specific surface area, and total pore volume of the hydrogel were turned out to be 103.7 μm, 60.70 m 2 /g and 0.0672 cm 3 /g, respectively. Adsorption results indicated that the maximum adsorption capacity occurred at the pH where SMZ was anionic and BPA was uncharged. When the adsorption temperature increased from 25 °C to 35 °C, the amount of adsorbed SMZ hardly changed, but that of BPA increased by two times. The adsorption capacity of the binary system (i.e., with both SMZ and BPA) was almost the same as that of the single system, indicating that simultaneous adsorption of SMZ and BPA was achieved. The adsorption equilibrium was reached quickly (within 5 min) for both SMZ and BPA. For adsorption isotherm, the Freundlich model fitted well for SMZ at 25, 35 and 45 °C. However, the adsorption of BPA exhibited the sigmoidally shaped isotherm at 25 °C with the Slips model fitting well, and both the Freundlich isotherm and the Slips isotherm fitted the data well at 35 °C and 45 °C, suggesting that the adsorption force was initially weak but greatly enhanced with an increase in adsorbate concentration or ambient temperature. The main adsorption mechanism was inferred to be electrostatic interactions for SMZ, and hydrophobic interactions as well as hydrogen bonding for BPA. The hydrogel adsorbent maintained favorable adsorption capacity for BPA after five adsorption-desorption cycles. These findings may provide a strategy for designing high performance adsorbents that can remove both hydrophilic and hydrophobic organic contaminants in the aquatic environment.
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Jing Zhang,Lingdong Chen,Biao Shen,Liqun Chen,Jie Feng
Hydrogels with good mechanical properties are promising for various applications. In this work, a simple yet effective method for preparing a novel double-network hydrogel was reported. First, nonfouling polymer, poly( N- (2-hydroxyethyl)acrylamide) (PHEAA), was crosslinked through covalent bonds. Antibacterial polysaccharide, chitosan (CS), was then crosslinked by chelation between the N- glucosamine units on the CS and citrate or sulfate ions. The poly( N- (2-hydroxyethyl)acrylamide)/chitosan double-network hydrogels (PHEAA/CS DN hydrogels) exhibited high tensile strength (3.8 MPa), strong elastic modulus (0.6 MPa). And the dynamic ionic crosslinking in CS network provided the DN gels with fast self-recovery ability as well as excellent fatigue resistance. Furthermore, the mechanical properties of the DN gels were enhanced after stretching and relaxing because of the molecular orientation and reconstruction of chitosan network. More importantly, the hydrogels have excellent antifouling and antibacterial properties, which is called “repelling and killing”, making them competitive candidates for applications in the biomedical field.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
·
IF 4.784
Yi Yuan,Xiaowei Xu,Jingni Gong,Ruojun Mu,Yuanzhao Li,Chunhua Wu,Jie Pang
Microspheres play an increasingly important role in the food and medicine industries. In this study, konjac glucomannan (KGM)/sodium alginate (SA)/graphene oxide (GO) solution was injected into CaCl 2 solution under high-voltage static electricity assistance to fabricate microspheres. Then, chitosan (CS) was coated on the surface of the microspheres to enhance their stability. SEM images confirmed that increasing voltage decreased the particle size of microspheres obviously. Furthermore, GO was beneficial in maintaining the full structure of freeze-dried microspheres, and the CS membrane improved the surface of the microspheres with no relatively obvious gully. Results indicated that KGM interacted with SA by hydrogen bond, and GO improved this interaction in microspheres. Furthermore, swelling tests showed that the microspheres exhibited different swelling properties in different media, and the CS membrane could improve the stability of microspheres in simulated intestinal fluid and simulated colon fluids. Moreover, GO could greatly improve the ciprofloxacin (CPFX) loading efficiency of microspheres, and achieving a sustained release effect of CPFX. Thus, CS-coated KGM/SA/GO microspheres showed great potential application in drug and/or nutrition factor colon-targeted delivery.
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Shouping Xu,Hao Li,Huan Ding,Zhouxiang Fan,Pihui Pi,Jiang Cheng,Xiufang Wen
Smart hydrogels with dual network were presented since a new allylated chitosan was conceived. As a double network hydrogel, its first network consisted of poly( N -isopropylacrylamide) worked as the gel matrix, and its second network with Schiff base bond enabled itself function as a molecular switch through the formation and break of the bond. When only the intestinal fluid was used, the second network could provide efficient protection for the loaded drug, and the drug release mechanism conformed to the non-Fickian type diffusion. While pre-treated with simulated gastric fluid, the switch would be opened and the mechanism was the Fickian type, which increased the cumulative percentage of drug release by about 25% and the release time by about 300 min. Besides, the hydrogel was characterized by 1 H NMR, FT-IR and SEM. The effects of allylated chitosan, pH and crosslinker on the swelling ratio and morphology of hydrogel were also studied.
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