Journal of Environmental Chemical Engineering
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2021
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IF 5.909
Bianyang He,Yaoyao Zhang,Bojie Li,Yuhan Chen,Lei Zhu
Carboxymethyl chitosan (CMCS) aerogels were prepared through sol-gel combining with freeze drying technology . The effects of CMCS concentration on the gelation time, volume shrinkage, density, porosity, compressive strength and hygroscopicity were investigated. Meanwhile, the CMCS aerogel was characterized by Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Then the CMCS aerogel was hydrophobic, modified through cold plasma modification technology, and oil absorbency of hydrophobic modified CMCS (HMCMCS) aerogel was researched. The results showed that the CMCS aerogel had the lowest density of 0.022 g/cm 3 , the maximum porosity of 95.34%, the highest compressive strength reached 1.74 MPa and a three-dimensional (3D) network heterogeneous porous structures in the inner areas. After hydrophobic modification, the water contact angle of 2% for HMCMCS aerogel with 20 min under 60 W reached 117 °. Besides, the HMCMCS aerogel represented excellent oil adsorbing property and outstanding recyclability , for the oil adsorption rate was up to 31.6 g/g and stable in multiple cycles.
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INDUSTRIAL CROPS AND PRODUCTS
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2021
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IF 5.645
Hongmei Yuan,Jianfei Wu,Dong Wang,Liulian Huang,Lihui Chen,Shan Lin
Regenerated cellulose (RC) films have numerous separation and purification applications. However, the mechanical properties of RC films are poor. Because of their very similar chemical structures and excellent compatibility, chitosan (CS) particles were chosen to reinforce bamboo-derived dissolving pulp (BP)-based films. BP/CS blend solutions were obtained by mixing BP and CS particles at different weight percentages into N-methyl-morpholine-N-oxide (NMMO) solvent. The BP/CS composite films prepared by the traditional phase transformation method formed a physically cross-linked network with high packing density for the water evaporation after air-drying. Due to the strong hydrogen bonding between CS and BP revealed by rheological properties and Fourier transform infrared (FTIR) data, the CS particles dispersed uniformly in the matrix, and the compatibility of the reinforcement with the matrix was excellent, which was further confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM) and UV–vis transmittance data. As the weight percentage of CS increased from 9.09 wt% to 14.24 wt%, the crystallinity of cellulose II increased from 32.20%–38.59%, and the tensile strength of the BP/CS composite films increased from 662.20 MPa to 865.53 MPa, respectively. These results indicate that the tensile strength of the BP/CS composite films was increased by nearly 250.83 %–358.56 % compared with that of the regenerated BP film (188.75 MPa). Moreover, the elongation at break was increased by 51.16 %-41.63 %. These findings provide a new way to prepare ultra-high-strength RC composite films.
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CARBOHYDRATE POLYMERS
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2021
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IF 9.381
Liqun Jiang,Mi Zhang,Yuting Bai,Feiyan Cui,Cong Zhang,Ziyao Wang,Sujia Si,Ling Yang,Yun Wang,Yudong Zhang,Lei Li,Shuo Liu,Xiangrong Wei,Yan Wang,Ya Xu,Jian Meng
The hypoxia in tumor microenvironment (TME) can upregulate the HIF-1α and PD-L1 expression and cause immunosuppression of tumor. In this study, a carboxymethyl chitosan-based pH/hypoxia-responsive and γ-Fe 2 O 3 /isosorbide dinitrate carrying micelle was designed, and it could catalyze endogenous H 2 O 2 to generate oxygen and relieve hypoxia in TME, so as to relieve the overexpression of HIF-1α and PD-L1 in tumor; meanwhile, it could react with H 2 O 2 to release ROS via Fenton reaction and induce cytotoxicity in tumor. Along with these multiple effects, this carboxymethyl chitosan-based micelles could provide a comprehensive strategy for tumor treatment.
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Food & Function
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2021
·Vol. 12
·期 20
·9947-9954
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IF 5.396
Huijuan Zheng,Weilin Liu,Shuibing Yang
Medium-chain fatty acids (MCFAs) have been proven as an easy energy source and active ingredient to prevent obesity and other metabolic disorders. However, the inherent hydrophobic nature of MCFAs causes poor aqueous solubility and dissolution in the gastrointestinal (GI) tract, thus limiting their applications in aqueous foods. To address these issues, a nutraceutical carrier system was developed by coating nanoliposomes with carboxymethyl chitosan (CMCS) through a series of well-designed processes, including thin-film hydration, dynamic high pressure microfluidization (DHPM) and surface modification. Electron microscopy investigation reveals an obvious morphology evolution from the uncoated nanoliposomes (UC-LPs) to the final CMCS coated nanoliposomes (CMCS-LPs). Together with the FTIR results, it confirms the successful coating of CMCS. More importantly, the resultant CMCS-LPs have a more negatively charged surface with a ζ-potential value of around −18.5 mV, which helps to increase the stability by avoiding severe particle aggregation. Owing to the above benefits, the encapsulated MCFAs can be safely retained in a long storage period of 90 days at 4 °C and the new carrier system also exhibits a more sustained release of MCFAs in the GI fluid.
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FOOD CHEMISTRY
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2021
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IF 7.514
Fang Li,Runqiang Liu,Volodymyr Dubovyk,Qiwen Ran,Bo Li,Yuqi Chang,Hongliang Wang,Hongyuan Zhao,Sridhar Komarneni
Herein, a simple, low-cost, environment-friendly strategy was proposed to prepare the composite of three-dimensional hierarchical porous carbon and chitosan, which was applied to modify the glass carbon electrode to fabricate an electrochemical sensor for the determination of niclosamide. The three-dimensional porous carbon with interconnected conductive network, high surface area, and self-generated oxygen-containing functional groups was prepared by salt-templating method with glucose as carbon source and eutectic mixture of LiBr/KBr as both activating and pore-forming agent. During the subsequent ultrasonic process, chitosan with excellent filming property, strong adsorption ability, and good dispersibility was successfully decorated on the obtained porous carbon to further enhance the determination performance of niclosamide. Benefitting from the multi-functional integration of three-dimensional hierarchical porous carbon and chitosan, the fabricated sensor presented a low limit of detection (6.7 nM) in the linear concentration range from 0.01 to 10 µM. Moreover, the fabricated sensor could show good repeatability, reproducibility, stability, and selectivity. Most important, the decent practicability for the detection of niclosamide was obtained in different food samples with low relative standard deviation and satisfactory recoveries. This work provides a very valuable reference for the sensitive determination of niclosamide in food samples.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
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IF 4.784
Yang Liu,Lishuang Hu,Bo Tan,Jingru Li,Xiaohui Gao,Yaning He,Xifeng Du,Wei Zhang,Weili Wang
Dextran-chitosan (DC) macromolecule resin was synthesized by ultrasonic heating and applied to adsorb various heavy metal ions (Cu 2+ , Co 2+ , Ni 2+ , Pb 2+ , Cd 2+ ). The morphology and structure of the samples were characterized by various testing methods. The effects of five factors on the adsorption properties were studied. The adsorption kinetics , thermodynamics and isotherm models were discussed theoretically. The results show that the adsorption of heavy metal ions by DC resin is a spontaneous single molecule chemical adsorption, and the adsorption capacities of DC resin for Cu 2+ , Co 2+ , Ni 2+ , Pb 2+ and Cd 2+ were 342 mg g −1 , 232 mg g −1 , 184 mg g −1 , 395 mg g −1 , and 269 mg g −1 , respectively at 20 °C, pH = 7 and adsorbent dose is 0.01 g. In addition, DC resin adsorbent has good reusability.
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Nanoscale
·
2019
·Vol. 11
·期 38
·17736-17745
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IF 6.97
Qian Zhu,Fushan Wang,Fengwei Zhang,Zhengping Dong
The direct oxidation of alcohols to esters through a green and cost-effective strategy is a fascinating chemical synthesis route. In this study, an environmentally friendly N-doped porous carbon encapsulated Co-based nano-catalyst was prepared via a simple carbonization procedure, utilizing renewable chitosan, accessible dicyandiamide and low-cost Co(OAc)2 as co-precursors. The obtained Co@NC-2-T catalysts were successfully used in selective oxidation of aromatic alcohols with methanol to esters under atmospheric reaction conditions. The Co@NC-2-900 catalyst (added with 2 g dicyandiamide and pyrolyzed at 900 °C) shows optimal activity and applicability and can also be reused at least six times in the oxidative esterification of aromatic alcohols with excellent stability. The presence of superoxide anion radicals in the current catalytic system was detected by the EPR method, and a possible mechanism of alcohol oxidation to ester was proposed on this basis. Thus, this study provides a facile, eco-friendly, and highly efficient catalytic system for oxidative esterification of alcohols.
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Polymers
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2019
·Vol. 11
·期 9
·1417
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IF 3.164
Wei Wang,Zufeng Xiao,Chaofan Huang,Kewang Zheng,Yin Luo,Yumin Dong,Zitong Shen,Wei Li,Caiqin Qin
Chitosan microspheres modified by 2-pyridinecarboxaldehyde were prepared and used in the construction of a heterogeneous catalyst loaded with nano-Cu prepared by a reduction reaction. The chemical structure of the catalyst was investigated by Fourier Transform Infrared Spectroscopy (FT-IR), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), and X-ray Photoelectron Spectroscopy (XPS). Under mild conditions, such as no ligand at room temperature, the catalyst was successfully applied to catalyze the borylation of α,β-unsaturated receptors in a water-methanol medium, yielding 17%–100% of the corresponding β-hydroxy product. Even after repeated use five times, the catalyst still exhibited excellent catalytic activity.Keywords:chitosan microspheres;copper;organoboron compounds
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CARBOHYDRATE POLYMERS
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2019
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IF 6.044
Xiao Ke,Mingyan Li,Xiaoqing Wang,Jiawen Liang,Xing Wang,Shaoyun Wu,Ming Long,Chengheng Hu
Acute myocardial infarction (MI) is a common cardiovascular disease with high mortality. In this study, an injectable thermosensitive hydrogel of chitosan (CS)/dextran (DEX)/β–glycerophosphate (β-GP) loaded with umbilical cord mesenchymal stem cells (UCMSCs) was prepared for MI treatment. The good biocompatibility of hydrogels was confirmed by 3T3 cells and HUVECs culture study in vitro . HUVECs encapsulated in the hydrogels showed a cell delivery ability. Furthermore, the results indicated that hydrogel could encapsulate most of UCMSCs and the cells exhibited good viability in CS/ 1.0DEX/β-GP hydrogels. The expression of cardiac markers of cTnI and Cx43 and signaling pathways of p-Akt and p-ERK1/2 were studied, and it showed that UCMSCs differentiate towards myocardium and has a great potential for therapeutic use of cardiac repair. In conclusion, the thermosensitive hydrogel of CS/1.0 DEX/β-GP loaded UCMSCs was a promising candidate as cell delivery vehicle for cardiac repair to reconstitute damaged myocardium.
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JOURNAL OF MATERIALS SCIENCE
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2019
·Vol. 55
·期 5
·2176-2185
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IF 3.442
Ghorbani Marjan,Nezhad-Mokhtari Parinaz,Sohrabi Hessamaddin,Roshangar Leila
In the last years, chitosan (CS) nanofibers as one of the biodegradable biomaterials in nature for tissue engineering and related fields, including wound healing and cell–material interaction, have been widely used. For this purpose, we prepared the reinforced CS/nanocrystals cellulose-graft-poly( N -vinylcaprolactam) (CS/NCC-g-PVCL) nanofibers via the electrospinning technique. Fabricated nanofibers were characterized and studied for their structural, morphological, thermal stability, as well as mechanical and hydrophilic properties. Uniform nanofibers were achieved, and NCC-g-PVCL contents were partially embedded into CS nanofibers, as revealed in SEM analyses. Incorporation of NCC-g-PVCL contents (0.5, 2.5, and 5 wt%) enhanced the average fiber diameter of the obtained nanofibers from 100 nm (neat CS) to ∼ 350 nm [CS/NCC-g-PVCL (5 wt%)] and improved the nanofibers thermal stability. Additionally, among the CS/NCC-g-PVCL nanocomposite fibers, those loaded with 5 wt% NCC-g-PVCL had the best mechanical properties. The water contact angle of nanocomposite nanofibers increased with elevation of the weight content of NCC-g-PVCL. Cell culture results showed that the prepared nanofibers had better cytocompatibility and proliferation than neat CS nanofibers. The results proposed that the developed CS/NCC-g-PVCL nanocomposite nanofibers were promising as new biomaterials to be applied in the area of skin tissue engineering.
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JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
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2019
·
IF 3.571
Xingchen Zhai,Shoujun Yuan,Xin Yang,Pan Zou,Linna Li,Guoyou Li,Yong Shao,A. M. Abd El-Aty,Ahmet Hacımüftüoğlu,Jing Wang
In recent years, various studies have confirmed the role of natural products as effective cancer prevention and treatment drugs. The present study demonstrated that chitosan oligosaccharide (COS) from shells of shrimp and crab caused an inhibitory effect on the proliferation of human renal carcinoma in vitro and in vivo. First, the in vivo biodistribution of COS was investigated by the synthesis of cyanine-7-labeled COS (COS–Cy7) following tail vein injection. The kidney was found to be a major target organ. Then, the impacts on renal carcinoma cell proliferation, apoptosis, and reactive oxygen species (ROS) production were observed in vitro, and an orthotopic xenograft tumor model was designed to evaluate the antitumor efficacy of COS in vivo. In renal carcinoma cells, COS induced G2/M phase arrest and apoptosis in a ROS-dependent fashion. COS significantly promoted mRNA expression of nuclear factor erythroid 2-related factor (Nrf2) and Nrf2 target genes, such as heme oxygenase 1, modifier subunit of glutamate cysteine ligase, and solute carrier family 7 member 11. Additionally, COS significantly upregulated the protein expression of glucose-regulated protein 78, protein RNA-like endoplasmic reticulum (ER) kinase, eukaryotic initiation factor 2α, activating transcription factor 4, C/EBP homologous protein, and cytochrome c, which justified the activation of the ER stress signaling pathway. In vivo, COS repressed tumor growth and induced apoptosis and ROS accumulation, consistent with the in vitro results. Taken together, COS repressed human renal carcinoma growth and induced apoptosis both in vitro and in vivo, mainly via ROS-dependent ER stress pathways.
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INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
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2019
·
IF 4.784
Lian Xing,Jinchen Sun,Huaping Tan,Guoliang Yuan,Jianliang Li,Yang Jia,Dangsheng Xiong,Guang Chen,Jianzhong Lai,Zhonghua Ling,Yong Chen,Xiaohong Niu
Hydrogels based scaffolds are very promising materials for a wide range of medical applications including tissue engineering and drug delivery. This study reports a covalently cross-linked composite hydrogel embedded with microspheres basing natural polysaccharides as a protein delivery system for soft tissue engineering. This biodegradable composite hydrogel derived from water-soluble chitosan and alginate derivatives upon mixing, without addition of chemical cross-linking agents. The gelation is attributed to the Schiff-base reaction between amino and aldehyde groups of N -succinyl chitosan ( N -Chi) and oxidized alginate (OAlg), respectively. Meanwhile, gel-like microspheres were prepared with a diameter of 2–10 μm by conjugating sodium alginate with Ca 2+ in an aqueous emulsion via the emulsion cross-linking technique. Bull Serum Albumin (BSA) was encapsulated into alginate gel microspheres and subsequently incorporated into OAlg/ N -Chi hydrogels to produce a composite scaffold. In the current work, gelation rate, morphology, mechanical properties, swelling ratio, in vitro degradation and BSA release of the composite scaffolds were examined. The results show that mechanical and stable properties of gel scaffolds can be significantly improved by embedding alginate microspheres. The alginate microspheres can serve as a filler to toughen the soft OAlg/ N -Chi hydrogels. Compressive modulus of composite gel scaffolds containing 0.5 mL volume of microspheres was 57.3 KPa, which was higher than the control hydrogel without microspheres. Moreover, the controlled release of BSA encapsulated within this composite hydrogels showed significantly lower rate when compared with control hydrogel or microspheres alone. These characteristics provide a potential opportunity to use this injectable composite gel scaffold in protein delivery and soft tissue engineering applications.
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