151
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Shao LJ, Wu J, Xu ZK. ELECTROSPRAYING/ELECTROSPINNING OF POLY(γ-STEARYL-L-GLUTAMATE): FORMATION OF SURFACES WITH SUPERHYDROPHOBICITY. CHINESE JOURNAL OF POLYMER SCIENCE 2009. [DOI: 10.1142/s0256767909003728] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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152
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Lv YY, Wu J, Wan LS, Xu ZK. Novel Porphyrinated Polyimide Nanofibers by Electrospinning. THE JOURNAL OF PHYSICAL CHEMISTRY C 2008. [DOI: 10.1021/jp7105549] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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153
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Wan LS, Ke BB, Wu J, Xu ZK. Catalase Immobilization on Electrospun Nanofibers: Effects of Porphyrin Pendants and Carbon Nanotubes. THE JOURNAL OF PHYSICAL CHEMISTRY C 2007. [DOI: 10.1021/jp070983n] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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154
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155
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Yang Q, Wu J, Li JJ, Hu MX, Xu ZK. Nanofibrous Sugar Sticks Electrospun from Glycopolymers for Protein Separation via Molecular Recognition. Macromol Rapid Commun 2006. [DOI: 10.1002/marc.200600470] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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156
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Wan LS, Wu J, Xu ZK. Porphyrinated Nanofibers via Copolymerization and Electrospinning. Macromol Rapid Commun 2006. [DOI: 10.1002/marc.200600381] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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157
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Ye P, Xu ZK, Wu J, Innocent C, Seta P. Nanofibrous poly(acrylonitrile-co-maleic acid) membranes functionalized with gelatin and chitosan for lipase immobilization. Biomaterials 2006; 27:4169-76. [PMID: 16584770 DOI: 10.1016/j.biomaterials.2006.03.027] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2005] [Accepted: 03/15/2006] [Indexed: 02/08/2023]
Abstract
Nanofibrous membranes with an average diameter of 100 and 180 nm were fabricated from poly(acrylonitrile-co-maleic acid) (PANCMA) by the electrospinning process. These nanofibrous membranes contain reactive groups which can be used to covalently immobilize biomacromolecules. Two natural macromolecules, chitosan and gelatin, were tethered on these nanofibrous membranes to fabricate dual-layer biomimetic supports for enzyme immobilization in the presence of 1-ethyl-3-(dimethyl-aminopropyl) carbodiimide hydrochloride (EDC)/N-hydroxyl succinimide (NHS). Lipase from Candida rugosa was then immobilized on these dual-layer biomimetic supports using glutaraldehyde (GA), and on the nascent PANCMA fibrous membrane using EDC/NHS as coupling agent, respectively. The properties of the immobilized lipases were assayed. It was found that there is an increase of the activity retention of the immobilized lipase on the chitosan-modified nanofibrous membrane (45.6+/-1.8%) and on the gelatin-modified one (49.7+/-1.8%), compared to that on the nascent one (37.6+/-1.8%). The kinetic parameters of the free and immobilized lipases, K(m) and V(max), were also assayed. In comparison with the immobilized lipase on the nascent nanofibrous membrane, there is an increase of the V(max) value for the immobilized lipases on the chitosan- and gelatin-modified nanofibrous membranes. Results also indicate that the pH and thermal stabilities of lipases increase upon immobilization. The residual activities of the immobilized lipases are 55% on the chitosan-modified nanofibrous membrane and 60% on the gelatin-modified one, after 10 uses.
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158
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Ye P, Xu ZK, Wu J, Innocent C, Seta P. Entrusting poly(acrylonitrile-co-maleic acid) ultrafiltration hollow fiber membranes with biomimetic surfaces for lipase immobilization. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcatb.2006.02.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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159
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Wang ZG, Xu ZK, Wan LS, Wu J, Innocent C, Seta P. Nanofibrous Membranes Containing Carbon Nanotubes: Electrospun for Redox Enzyme Immobilization. Macromol Rapid Commun 2006. [DOI: 10.1002/marc.200500885] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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160
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Wu J, Jiang XL, Zhang HL. Synthesis of Diaryl Ether-Linked Porphyrin Dimers via Ullmann Coupling Reaction. HETEROCYCLES 2006. [DOI: 10.3987/com-06-10816] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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161
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Ye P, Xu ZK, Wu J, Innocent C, Seta P. Nanofibrous Membranes Containing Reactive Groups: Electrospinning from Poly(acrylonitrile-co-maleic acid) for Lipase Immobilization. Macromolecules 2005. [DOI: 10.1021/ma0517998] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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162
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Ye P, Xu ZK, Che AF, Wu J, Seta P. Chitosan-tethered poly(acrylonitrile--maleic acid) hollow fiber membrane for lipase immobilization. Biomaterials 2005; 26:6394-403. [PMID: 15919112 DOI: 10.1016/j.biomaterials.2005.04.019] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2005] [Accepted: 04/07/2005] [Indexed: 02/08/2023]
Abstract
A protocol was used to prepare a dual-layer biomimetic membrane as support for enzyme immobilization by tethering chitosan on the surface of poly(acrylonitrile-co-maleic acid) (PANCMA) ultrafiltration hollow fiber membrane in the presence of 1-ethyl-3-(dimethylaminopropyl) carbodiimide hydrochloride (EDC)/N-hydroxylsuccin-imide (NHS). The chemical change of the chitosan-modified PANCMA membrane surface was confirmed with Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. Lipase from Candida rugosa was immobilized on this dual-layer biomimetic membrane using glutaraldehyde (GA), and on the nascent PANCMA membrane using EDC/NHS as coupling agent. The properties of the immobilized enzymes were assayed and compared with those of the free one. It was found that both the activity retention of the immobilized lipase and the amount of bound protein on the dual-layer biomimetic membrane (44.5% and 66.5 mg/m2) were higher than those on the nascent PANCMA membrane (33.9% and 53.7 mg/m2). The kinetic parameters of the free and immobilized lipases, Km and Vmax, were also assayed. The Km values were similar for the immobilized lipases, while the Vmax value of the immobilized lipase on the dual-layer biomimetic membrane was higher than that on the nascent PANCMA membrane. Results indicated that the pH and thermal stabilities of lipase increased upon immobilization. The residual activity of the immobilized lipase after 10 uses was 53% on the dual-layer biomimetic membrane and 62% on the nascent PANCMA membrane.
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163
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Yang Q, Xu ZK, Hu MX, Li JJ, Wu J. Novel Sequence for Generating Glycopolymer Tethered on a Membrane Surface. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2005; 21:10717-23. [PMID: 16262342 DOI: 10.1021/la051797g] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Cell surface carbohydrates, usually binding with other biomacromolecules (such as lipids and proteins), are involved in numerous biological functions, including cellular recognition, adhesion, cell growth regulation, and inflammation. Synthetic carbohydrate-based polymers, so-called glycopolymers, are emerging as important well-defined tools for investigating carbohydrate-based biological processes and for simulating various functions of carbohydrates. In this study, a novel two-step sequence for the generation of a glycopolymer layer tethered on a polypropylene microporous membrane is described. First, a UV-induced graft polymerization of 2-aminoethyl methacrylate hydrochloride (AEMA) was carried out on the membrane to generate an amino-functionalized surface, and the effects of polymerization factors (monomer/initiator concentration and UV irradiation time) on the grafting density were studied. Second, sugar moieties were bound with the grafted functional layer to form glycopolymer by the reaction between the amino groups on the membrane surface and carbohydrate lactones. Chemical analysis by Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy combined with surface morphology observation by scanning electron microscopy confirmed the graft polymerization of AEMA and the formation of glycopolymer. The decreases of water contact angle and protein adsorption on the membrane revealed the enhancement of hydrophilicity and protein resistance due to the typical characteristics of the glycopolymer tethered on the surface. These results indicated that the novel sequence reported in this work is a facile process to form glycopolymer-modified surfaces.
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164
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Deng HT, Xu ZK, Dai ZW, Wu J, Seta P. Immobilization of Candida rugosa lipase on polypropylene microfiltration membrane modified by glycopolymer: hydrolysis of olive oil in biphasic bioreactor. Enzyme Microb Technol 2005. [DOI: 10.1016/j.enzmictec.2005.01.025] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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165
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Xu ZK, Nie FQ, Qu C, Wan LS, Wu J, Yao K. Tethering poly(ethylene glycol)s to improve the surface biocompatibility of poly(acrylonitrile-co-maleic acid) asymmetric membranes. Biomaterials 2005; 26:589-98. [PMID: 15282137 DOI: 10.1016/j.biomaterials.2004.03.008] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2003] [Accepted: 03/13/2004] [Indexed: 02/08/2023]
Abstract
To improve the surface biocompatibility, asymmetric membranes fabricated from poly(acrylonitrile-co-maleic acid)s (PANCMAs) synthesized by water-phase precipitation copolymerization were tethered (or immobilized) with poly(ethylene glycol)s (PEGs) by esterification reaction. Chemical changes on the membrane surface were characterized by Fourier transform infrared spectroscopy and elemental analysis to confirm the immobilization of PEG onto the PANCMA membranes. The hydrophilicity and blood compatibility of the PEG-tethered PANCMA membrane were investigated by water contact angle, water absorption, protein adsorption, plasma platelets adhesion and cell adhesion measurements, and the results were compared with the corresponding PANCMA membranes. It was found that, after the tethering of PEG, the hydrophilicity of the membrane can be improved significantly, and the protein adsorption, platelets adhesion and macrophage attachment on the membrane surface are obviously suppressed. Furthermore, not only the content of maleic acid in PANCMA, which influences the tethering density of PEG, but also the molecular weight of PEG has great effect on the surface modification of PANCMA membranes for biocompatibility.
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166
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Surface modification of polypropylene microfiltration membranes by the immobilization of poly(N-vinyl-2-pyrrolidone): a facile plasma approach. J Memb Sci 2005. [DOI: 10.1016/j.memsci.2004.10.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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167
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Ye P, Xu ZK, Wang ZG, Wu J, Deng HT, Seta P. Comparison of hydrolytic activities in aqueous and organic media for lipases immobilized on poly(acrylonitrile-co-maleic acid) ultrafiltration hollow fiber membrane. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.molcatb.2004.11.005] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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168
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Wu J, Zhang HL, Shi WM. Regiospecific Aryl Nitration of meso-Tetraarylporphyrins: The Directive Effect of para-Substituent. HETEROCYCLES 2005. [DOI: 10.3987/com-05-10555] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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169
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YE H. Fast iterative approach to the difference scattering from a dielectric target above a rough surface. SCIENCE IN CHINA SERIES G 2005. [DOI: 10.1360/142005-200] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
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170
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Xu ZK, Yang Q, Kou RQ, Wu J, Wang JQ. First results of hemocompatible membranes fabricated from acrylonitrile copolymers containing sugar moieties. J Memb Sci 2004. [DOI: 10.1016/j.memsci.2004.06.020] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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171
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Deng HT, Xu ZK, Huang XJ, Wu J, Seta P. Adsorption and Activity of Candida rugosa Lipase on Polypropylene Hollow Fiber Membrane Modified with Phospholipid Analogous Polymers. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2004; 20:10168-73. [PMID: 15518509 DOI: 10.1021/la0484624] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Efforts have recently been made toward the study of interactions of phospholipid with various enzymes. It seems that phospholipids may be directly involved in regulating the enzyme activity. In this work, three phospholipid analogous polymers (PAPs), containing hydrophobic octyloxy, dodecyloxy, and octadecyloxy groups (abbreviated as 8-PAP, 12-PAP, and 18-PAP, respectively), were tethered on polypropylene hollow fiber microfiltration membrane (PPHFMM) to create a biocompatible interface for lipase immobilization. Lipase from Candida rugosa was immobilized on these PPHFMMs by adsorption. The adsorption capacity, activity, and thermal stability of enzyme on the PAP-modified PPHFMMs were compared with those of enzyme on the nascent ones. It was found that, as for the PAP-modified PPHFMMs, the adsorption capacities of lipase are lower than that of the nascent ones, while the activity retention of immobilized lipase increases from 57.5% to 74.1%, 77.5%, and 83.2% respectively for the 8-PAP-, 12-PAP-, and 18-PAP-modified PPHFMMs. In addition, the experimental results of thermal stability show that the residual activity of the immobilized lipase at 50 degrees C for 2 h is 62% for the 8-PAP-modified PPHFMM, 59% for the 12-PAP-modified PPHFMM, and 66% for the 18-PAP-modified PPHFMM, which are also higher than that of the nascent ones.
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172
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Deng HT, Xu ZK, Liu ZM, Wu J, Ye P. Adsorption immobilization of Candida rugosa lipases on polypropylene hollow fiber microfiltration membranes modified by hydrophobic polypeptides. Enzyme Microb Technol 2004. [DOI: 10.1016/j.enzmictec.2004.07.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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173
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Liu ZM, Xu ZK, Wang JQ, Wu J, Fu JJ. Surface modification of polypropylene microfiltration membranes by graft polymerization of N-vinyl-2-pyrrolidone. Eur Polym J 2004. [DOI: 10.1016/j.eurpolymj.2004.05.020] [Citation(s) in RCA: 64] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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