FOOD CHEMISTRY
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2022
·
IF 9.231
Yan-Wei Liu,Ying Zhou,Guo-Qing Huang,Li-Ping Guo,Xiao-Dan Li,Jun-Xia Xiao
Coacervation of the lipase from Aspergillus oryzae (AOL) with chitosan was a feasible way to fabricate lipase-loaded particles and the optimum conditions were phase separation pH 5.5, chitosan to AOL mass ratio 1:5, and temperature 25 °C in the absence of NaCl, which conferred an AOL loading efficiency of up to 95.48% and activity recovery of 69.60%. The AOL-chitosan coacervates were highly porous and more susceptible to weight loss upon heating. Coacervation with chitosan increased the activity of AOL and shifted its optimum pH from 7.0 to 6.0, but exerted no effect on its optimum temperature (45 °C). Thermal deactivation kinetics analysis revealed that the coacervated AOL was more thermal stable, while the Michaelis-Menten kinetics analysis indicated that coacervation with chitosan increased the V max of AOL by 2.4 folds, but decreased its substrate affinity by 3.6 folds. Hence, the AOL-chitosan coacervates are potential in the construction of Pickering emulsion-based lipase catalysis systems.
研究领域:
生物化学
·
酶工程
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DOI
高影响因子
RSC Advances
·
2017
·Vol. 7
·期 14
·8542-8549
·
IF 3.108
Zhenliang Li,Zunli Mo,Shujuan Meng,Huhu Gao,Xiaohui Niu,Ruibin Guo,Taibao Wei
A simple chiral electrochemical sensor based on hydroxypropyl chitosan (HPCS) covalently bound to multi-walled carbon nanotubes (MWCNTs) was developed for the recognition of mandelic acid (MA) enantiomers. HPCS preferably combines with (S)-MA over (R)-MA, which was attributed to the favorable host–guest interactions between HPCS and the MA enantiomers. In addition, the recognition efficiency was significantly increased after hydroxypropyl groups were grafted onto chitosan (CS), which may be due to a stereo-hindrance effect. Moreover, the electrochemical recognition of amino acid enantiomers was investigated; the functional groups of the enantiomers play an important role in the enantioselective discrimination.
研究领域:
生物化学
·
材料科学
·
分析化学
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DOI
高影响因子
RSC Advances
·
2011
·Vol. 1
·期 2
·282-289
·
IF 0
Xueying Qiu,Yuhong Yang,Liping Wang,Shanling Lu,Zhengzhong Shao,Xin Chen
Time-evolved gelation behavior of a chitosan-β-glycerophosphate (CS/β-GP) system was elucidated from rheological investigation, NMR analysis, fluorescence measurement, and morphology observation. Urea and isobutanol were selected to assess the interactions between the two components during the gelation process of the CS/β-GP system. Urea was found to be detrimental to the gelation process by both disrupting hydrogen bonding and retarding the formation of hydrophobic domains. On the contrary, the addition of isobutanol accelerated the sol–gel transition by strengthening the hydrophobic interactions. These results reveal that both hydrogen bonding and hydrophobic interactions within chitosan or between chitosan and β-glycerophosphate molecules are the main reasons for gel formation. The results also indicate that firstly the formation of hydrogen bonds makes the hydrophobic sites more accessible, and then the synergistic hydrogen bonding and hydrophobic interactions lead to the final formation of CS/β-GP gel network. This work demonstrates the possibility of tuning the gelling ability as well as the mechanical properties of CS/β-GP hydrogels. Thus, it gives the opportunities to optimize the performance of this promising natural thermosensitive material for practical applications in the future.
研究领域:
材料科学
·
生物医学工程
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DOI
LWT-FOOD SCIENCE AND TECHNOLOGY
·
2022
·
IF 6.056
Alkassoumi Hassane Hamadou,Jiyao Zhang,Chen Chao,Bin Xu
This work evaluated the effect of pectin (P) and chitosan (CH) dual coating on rutin (R) loaded nanoliposomes (NLs). Besides R loaded NLs (RNLs), CH coated RNLs (CH-RNLs) and P coated CH-RNLs (P–CH-RNLs) were prepared. The results showed a size increase of NLs due to the polymer coatings, confirming a successful deposition of CH and P onto the surfaces of NLs. A surface charge reversal was observed after coating RNLs and CH-RNLs with CH and P, respectively. The coating resulted in a significant decrease in encapsulation efficiency (EE) from 88.19% in RNLs to 78.89% in CH-RNLs and 73.44% in P–CH-RNLs. Due to protection provided by the P–CH barrier, P–CH-RNLs displayed better thermal, pH, ionic and oxidative stability. NLs were more stable at 4 °C as compared to 25 °C over 8 weeks, and P–CH-RNLs exhibited the best performance overall. This study revealed P–CH coating as a potential route to produce stable NLs for the delivery of hydrophobic rutin.
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DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 140
·期 3
·e53318
·
IF 3.057
Aoqi Li,Yingqing Ye,Peixin Gong,Bo Xiao,Bo Jiang
Compared with traditional conjugates 1-ethyl-3-(3-dimethyl aminopropyl) carbodiimide (EDC) and N-hydroxysuccinimide (NHS), 4-(4,6-dimethoxy-1,3,5-triazin-2-yl)-4-methylmorpholinium chloride (DMTMM) is an emerging biological coupling reagent and has been used in the amidation of hyaluronic acid. In this paper, DMTMM was used to achieve the amidation of chitosan (CS) with glucuronic acid (GA) in an aqueous medium to generate a GA-CS derivative. The grafting efficacy was preliminarily compared with the EDC/NHS-mediated reaction. As a result, the substitution degree of 17.6% for DMTMM-mediated grafting and 13.1% for EDC/NHS chemistry indicated that DMTMM-mediated synthesis of GA-CS appeared to be more efficient. The reaction kinetics experiments showed that GA-CS derivative with a degree of substitution up to about 26.1% was obtained using equal molar ratios of DMTMM and GA exceeding CS at room temperature. These results indicate that employing DMTMM as a coupling agent is a feasible and promising strategy for the amidation modification of chitosan.
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DOI
高影响因子
Science China-Technological Sciences
·
2022
·Vol. 65
·期 5
·1029-1042
·
IF 3.903
Shi MingYue,Jiang LiJie,Yu ChaoJie,Dong XiaoRu,Yu QingYu,Yao MengMeng,He ShaoShuai,Yue ZhiWei,Yao FangLian,Zhang Hong,Sun Hong,Li JunJie
Currently, it is a challenge to develop hemostatic materials with high water absorption capacity and anti-fatigue properties for quickly preventing massive hemorrhage from arteries and visceral organs. A series of polyacrylic acid/chitosan (PAA/CS) cryogels were prepared by a cryostructurization technique to improve mechanical performance and hemostatic efficiency of chitosan (CS). In this system, the chemically cross-linked PAA network was used as a framework to improve water absorption behaviors and mechanical strength. The CS network was co-blended by hydrogen bonding and electrostatic interactions, both of which synergistically promoted hemostasis. These cryogels had high porosity (>94%), rapid water absorption rate (<3 s), high blood absorption capacity (>2000%), outstanding mechanical strength, and fatigue resistance. Moreover, the results of cytotoxicity and hemolysis demonstrated that the cryogels had good biocompatibility. Notably, the PAA/CS cryogels exhibited superior whole blood coagulation ability and red blood cell and platelet adhesion ability compared to those of commercial hemostatic dressing (gauze, gelatin sponges, and CS sponges). Based on these results, mouse femoral artery hemorrhage models and liver hemorrhage models were prepared to investigate the hemostatic ability of the prepared PAA/CS cryogels. Results suggested that the hemostatic ability of PAA 5 /CS cryogels was superior to that of commercial hemostatic materials. Therefore, the PAA/CS cryogels showed potential application in preventing massive hemorrhage from arteries and visceral organs.
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高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2022
·
IF 8.025
Wentao Shi,Xuan Zhang,Lu Bian,Yao Dai,Zhe Wang,Yanjun Zhou,Shuang Yu,Zhijian Zhang,Peng Zhao,Hong Tang,Qing Wang,Xiaojie Lu
Here, we evaluated osteogenic differentiation in vitro and new bone formation in vivo using an alendronate-loaded chitosan/polycaprolactone scaffold (CS/PCL) in rats with a critical-sized calvarial defect. Through the action of genipin, which has a crosslinking function, alendronate (AL) was anchored throughout the CS/PCL composite scaffold (CS/ [email protected] ) to form an AL sustained release system. We demonstrated that CS/ [email protected] scaffolds significantly enhanced the osteogenic differentiation of ectomesenchymal stem cells (EMSCs) in vitro. Additionally, we explored the possible molecular mechanism of CS/ [email protected] scaffolds in the osteogenic differentiation of EMSCs. This composite scaffold exerted two positive effects on EMSC osteogenic differentiation: 1) the CS/ [email protected] scaffold enhanced EMSC osteogenic differentiation by upregulating bone morphogenetic protein 2, interleukin 10 and laminin expression; and 2) the CS/ [email protected] scaffold promoted the osteogenic differentiation of EMSCs by activating the yes-associated protein (YAP) signaling pathway. YAP and its downstream target transglutaminase are crucial mediators in the osteogenic differentiation of EMSCs. Finally, micro-computed tomography analyses and histology results suggested that the CS/ [email protected] scaffold exhibited a superior capacity to accelerate new and mature bone formation in skull bone defects in Sprague–Dawley rats. This simple and low-cost technology may represent a promising strategy to construct an efficient delivery system to repair bone defects.
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DOI
PubMed
高影响因子
CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Ming Jiang,Yuanzhong Pan,Yuanda Liu,Kai Dai,Qinghao Zhang,Jing Wang
Bone regeneration and vascularization have presented a clinical challenge for decades. Considering the importance of stem cells, such as mesenchymal stem cells (MSCs), in bone regeneration, endothelial progenitor cells (EPCs) are crucial during bone repair . This paper presented sulfated chitosan (SCS)-based hydrogel scaffolds to accelerate bone tissue regeneration , vascularization enhancement, and improve bone repair. Thus, these scaffolds played a crucial role in the regeneration of blood vessels, with the increased presentation of epithelial progenitors and immune cells in this microenvironment. In vivo experiments showed that the biological impact of SCS was critical for angiogenesis and vascularization, in conjunction with bone morphogenetic protein-2 (BMP-2) and MSCs. Therefore, the BMP-2-/hydrogel system established in this study promoted angiogenesis, stimulated MSC proliferation , and enhanced bone tissue formation. In addition, this paper highlighted the angiogenic role of SCS in creating a micro-environment for effective bone repair and provides insight into the future development of new bone regeneration material.
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DOI
PubMed
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Femiana Gapsari,Djarot B. Darmadi,Hans Juliano,Syarif Hidayatullah,Suteja,Sanjay Mavinkere Rangappa,Suchart Siengchin
Natural fibers are available as an essential substitute for synthetic fiber in many applications. However, the sensitivity of Chinese Windmill Palm or Trachycarpus Fortune Fiber (TFF) to water causes low interfacial bonding between the matrix and the fiber and at the end reduces the mechanical properties of the composite product. Alkaline treatment improves mechanical properties and does not affect water absorption. Hence, additional treatment in the coating is required. This study uses alkaline treatment and coating modification using blended chitosan and Acrylated Epoxidized Soybean Oil (AESO). Blend coating between AESO and chitosan is performed to increase water absorption and mechanical properties. TFF water resistance improved significantly after the coating, with water absorption of the alkaline/blend coating-TFF of 3.98 % ± 0.52 and swell ability of 3.156 % ± 0.17. This indicated that blend coating had formed a cross-link of fiber and matrix after alkalization. Thus, the single fiber tensile strength increased due to the alkaline treatment, and water absorption decreased due to the coating. The combination of alkaline treatment and blend coating on TFF brings excellent properties, as shown by the increase in tensile strength in both single fiber test and composite.
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DOI
PubMed
高影响因子
Crystals
·
2023
·Vol. 13
·期 5
·755
·
IF 2.7
Xueli Mei,Shihao Li,Yaoyao Chen,Xueli Huang,Yali Cao,Vitaliy P. Guro,Yizhao Li
The dissipation of energy in the form of heat causes a huge energy loss across the globe. Thermal insulation materials which reduce heat loss can alleviate the energy crisis. Among many thermal insulation materials, silica aerogels (SAs) have attracted extensive attention due to their high surface area, low density and low thermal conductivity. However, the applications of SAs are restricted by their mechanical fragility. In this paper, a series of different ratios of silica–chitosan composite aerogels (SCAs) were prepared by mixing sodium silicate aqueous solution and chitosan solution followed by freeze drying. The surface morphology of SAs, CAs and SCAs was studied by scanning electron microscopy (SEM). The specific surface area, pore volume and pore size of the composite aerogels were studied by N2adsorption–desorption isotherms. The thermal conductivities, chemical structures, thermal stabilities and hydrophobicities of SAs, CAs and SCAs were tested and analyzed. In addition, the adsorption properties of SCAs were measured using different organic solvents. The results reveal that when the proportion of sodium silicate aqueous solution and chitosan solution is 1:1, the obtained SCA−1/1 has the best performance, with a low thermal conductivity of 0.0369 W/m·K, a large specific surface area of 374.7 m2/g, and good thermal stability. In addition, the prepared SCAs also have good hydrophobicity and absorption properties, with adsorption capacities of 6.7–9.4 g/g, which show great application potential in the fields of insulation and adsorption.
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高影响因子
JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY
·
2023
·Vol. 333
·期 1
·71-84
·
IF 1.6
Du Zhiyuan,Ni Yuran,Peng Hao,Tang Mei,Li Yuanli,Lv Lina,Li Xiaoyu,Chi Fangting
Novel chitosan crosslinked amidoxime polyacrylonitrile aerogel was synthesized and used for adsorption of uranium from seawater. The effects of initial uranium concentration, contact time, and pH value on uranium adsorption were investigated. The simulated uranium solution adsorption experiment shows that under the condition of an initial uranium concentration of 100 mg/L, the maximum adsorption capacity of CTS-g-PAO is 203.4 mg/g. The adsorption process can be well-fitted by Freundlich and Pseudo-second order models. In addition, CTS-g-PAO aerogel has good antibacterial activity against marine bacteria, with the antibacterial activity reaching 94.8%. The results demonstrated that CTS-g-PAO aerogel was an effective adsorbent for extracting uranium from seawater.
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DOI
高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
·
2014
·
IF 4.287
Fang Yuan,Shasha Wang,Gaojian Chen,Kehua Tu,Hongliang Jiang,Li-Qun Wang
A novel approach to design pH-sensitive and disintegrable polyelectrolyte nanogels composed of citraconic-based N -(carboxyacyl) chitosan (polyanion) and quaternary chitosan (polycation) was reported. Firstly, the hydrolysis of citraconic-modified chitosan was monitored using fluorescamine assay and it could selectively dissociate in acidic media (e.g., pH ∼5.0) due to the isomerization during the addition of citraconic anhydride to chitosan. Secondly, the self-assembly behaviors of different polyelectrolyte pairs between citraconic-based chitosan and quaternary chitosan were investigated via colloidal titration assay. It was indicated that the difference in molecular weight (MW) of opposite charged polyelectrolytes played an important role on the formation of polyelectrolyte nanogels. Results showed that polyelectrolyte nanogels (ca. 300 nm in size) only formed when polyanion and polycation had a very large difference in MW. The pH-sensitive behavior of polyelectrolyte nanogels was comprehensively investigated by dynamic light scattering (DLS) and transmission electron microscope (TEM). The incorporation of charge-conversional citraconic-based chitosan into polyelectrolyte complexes has provided an effective approach to prepare polyelectrolyte nanogels which were very stable at neutral pH but disintegrated quickly in acidic media.
研究领域:
材料科学
·
生物医学工程
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）