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Electrospinning of polycarbonate urethane biomaterials

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Frontiers of Chemical Science and Engineering 2011年第1期5卷 11-18页

作者： Yakai FENG Fanru MENG Ruofang XIAO Haiyang ZHAO jintang guo School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

Polycarbonate urethane(PCU)nano-fibers were fabricated via electrospinning using N,Ndimethylformamide(DMF)and tetrahydrofuran(THF)as the mixed *** effect of volume ratios of DMF and THF in the mixed solvent on the fiber structures was *** results show that nano-fibers with a narrow diameter distribution and a few defects were obtained when mixed solvent with the appropriate volume ratio of DMF and THF as 1∶*** the proportion of DMF was more than 75%in the mixed solvent,it was easy to form many beaded *** applied voltage in the electrospinning process has a significant influence on the morphology of *** the electric voltage was set between 22 and 32 kV,the average diameters of the fibers were found between 420 and 570 *** electron microscopy(SEM)images showed that fiber diameter and structural morphology of the electrospun PCU membranes are a function of the polymer solution *** the concentration of PCU solution was 6.0 wt-%,a beaded-fiber microstructure was *** increasing the concentration of PCU solutions above 6.0 wt-%,beaded fiber decreased and finally ***,when the PCU concentration was over 14.0 wt-%,the average diameter of fibers became large,closed to 2μm,because of the high solution *** average diameter of nanofibers increased linearly with increasing the volume flow rate of the PCU solution(10.0 wt-%)when the applied voltagewas 24 *** results show that the morphology of PCU fibers could be controlled by electrospinning parameters,such as solution concentration,electric voltage and flow rate.

关键词： electrospinning polycarbonate urethane process parameter average diameter morphology

Preparation and Investigation of High-Efficiency Antibacterial Liquid Dishwashing Detergent

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Transactions of Tianjin University 2019年第4期25卷 322-329页

作者： Mingxue Dai jintang guo Xuexue Xue Yakai Feng School of Chemical Engineering and Technology Tianjin University

A high-effi ciency liquid dishwashing detergent was prepared by using oregano essential oil as an antibacterial agent. The surface cleaning and antibacterial property of the detergent resolved its unifunctionality problem. The antibacterial activities of the detergent were demonstrated through a disk diff usion assay and wipe experiments with Escherichia coli and Staphylococcus aureus . Results showed that the prepared detergent was highly eff ective against E. coli and S. aureus . The results of chemical accelerated tests indicated that the detergent would be eff ective for at least 1 year. The antibacterial property and detergency performance of the high-effi ciency antibacterial liquid dishwashing detergent were compared with those of a commercial antibacterial detergent containing 0.02% o -phenylphenol. The detergency performance of the high-effi ciency detergent reached 97.8% and was superior to that of the commercial antibacterial detergent.

关键词： Oregano essential oil Dishwashing detergent Antibacterial property Detergency performance

Copolymerization of polyketones catalyzed by polyacrylonitrile resin-supported palladium acetate

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Frontiers of Chemical Science and Engineering 2008年第2期2卷 165-170页

作者： jintang guo Hongxin ZHANG Bo WANG Yaqin YE School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

The crosslinked polyacrylonitrile (PAN) wassynthesized by suspension polymerization using acrylonitrile(ANT) and divinylbenzene (DVB). Effects of a varietyof conditions on the polymerization of PAN particle sizeand stiffness were investigated. Polyketone was preparedby the copolymerization of carbon monoxide (CO) andstyrene (ST) catalyzed by PAN resin-supported palladiumacetate. The resin-supported catalyst and the copolymerizationproduct were characterized by infrared spectroscopy(IR) and Scanning Electron Microscopy (SEM). Effects ofthe components of a catalytic system and reaction time onthe catalytic activity were studied. The reusability of theresin-supported catalyst was also *** indicatedthat the resin-supported catalyst has excellent catalyticproperty. The yield of polyketone was 6.2348 g whenusing 1 g of resin and 22.4 mg of palladium acetate.

关键词： PAN supported catalyst carbon monoxide styrene polyketone

Synthesis of Novel Electron Donors and Their Application to Propylene Polymerization

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Transactions of Tianjin University 2012年第1期18卷 8-14页

作者： guo jintang HU Guang CHEN Zhikun School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

A series of electron donors,including 1,1-cyclopentanecarboxylic acid diethyl ester (CPCADEE),1,1cyclopentanedimethanol acetic diester (CPDMAD),1,1-biethoxymethyl pentane (BEMP),2,2-diethyl diethylmalonate (DEDEM)and 2,2-diethyl-1,3-propanediol acetic diester (DEPDADE),were synthesized by diethyl malonate (DEM).The purities and structures of the above products were characterized by gas chromatography (GC) and gas chromatography-mass spectrometer (GC-MS),***,the possible optimal three-dimensional structures of these donors were simulated by means of Gaussian 03 and Chem *** these electron donors were coordinated with tetrachloro titanium (TiCl 4) and chloride magnesium (MgCl 2)to obtain the catalysts for the polymerization of *** catalytic activities and properties of polypropylene are greatly improved by adding external donor(ED) when CPCADEE or DEPDADE is used as internal donor(ID).However,when BEMP was used as ID,the highest catalytic activity is obtained without adding ED,which can reduce production costs and simplify catalytic *** experiments indicate that BEMP has the shortest distance of oxygen atoms and the highest electronegativity.

关键词： electron donor structural simulation propylene polymerization 1,1-biethoxymethyl pentane

Surface modification of biomaterials by photochemical immobilization and photograft polymerization to improve hemocompatibility

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Frontiers of Chemical Science and Engineering 2010年第3期4卷 372-381页

作者： Yakai FENG Haiyang ZHAO Li ZHANG jintang guo School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China

Thrombus formation and blood coagulation are serious problems associated with blood contacting products,such as catheters,vascular grafts,artificial hearts,and heart *** progresses and strategies to improve the hemocompatibility of biomaterials by surface modification using photochemical immobilization and photograft polymerization are reviewed in this *** approaches to modify biomaterial surfaces for improving the hemocompatibility,i.e.,bioinert surfaces,immobilization of anticoagulative substances and biomimetic surfaces,are *** biomimetic amphiphilic phosphorylcholine and Arg-Gly-Asp(RGD)sequence are the most effective and most often employed biomolecules and peptide sequence for improving hemocompatibility of material *** RGD sequence can enhance adhesion and growth of endothelial cells(ECs)on material surfaces and increase the retention of ECs under flow shear stress *** surface modification is a promising strategy for biomaterials especially for cardiovascular grafts and functional tissue engineered blood vessels.

关键词： anticoagulative biomimetic biomaterials hemocompatibility phosphorylcholine photochemical immobilization photograft polymerization photolinker surface modification

Multifunctional peptide conjugated amphiphilic cationic copolymer for enhancing ECs targeting, penetrating and nuclear accumulation

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Frontiers of Chemical Science and Engineering 2020年第5期14卷 889-901页

作者： Xinghong Duo Lingchuang Bai Jun Wang jintang guo Xiangkui Ren Shihai Xia Wencheng Zhang Abraham Domb Yakai Feng School of Chemical Engineering and Technology Tianjin UniversityTianjin 300350China School of Chemistry and Chemical Engineering Qinghai University for NationalitiesXining 810007China Collaborative Innovation Center of Chemical Science and Chemical Engineering(Tianjin) Tianjin 300350China Key Laboratory of Systems Bioengineering(Ministry of Education) Tianjin UniversityTianjin 300072China Department of Hepatopancreatobiliary and Splenic Medicine Afiliated HospitalLogistics University of People's Amed Police ForceTianjin 300162China Department of Physiology and Pathophysiology Logistics University of People's Armed Police ForceTianjin 300162China Institute of Drug Research(IDR) School of Pharmacy Faculty of MedicineThe Hebrew University of JerusalemJerusalem 91905Israel

Gene therapy has drawn great attention in the treatments of many diseases,especially for cardiovascular ***,the development of gene carriers with low cytotoxicity and multitargeting function is still a ***,the multitargeting REDV-G-TATG-NLS peptide was conjugated to amphiphilic cationic copolymer poly(e-caprolactone-co-3(S)-methyl-morpho-line-2,5-dione)-g-polyethyleneimine(PCLMD-g-PEI)via a heterobifunctional orthopyridyl disulfde-poly(ethylene glycol)-N-hydroxysuccinimide(OPSS-PEG-NHS)linker to prepare PCLMD-g-PEI-PEG-REDV-G-TAT-G-NLS copolymers with the aim to develop the gene carriers with low cytotoxicity and high transfection *** multitargeting micelles were prepared from PCLMD-g-PEI-PEG-REDV-G-TAT-G-NLS copolymers by self-assembly method and used to load pEGFP-ZNF580 plasmids(pDNA)to form gene complexes for enhancing the proliferation and migration of endothelial cells(ECs).The loading pDNA capacity was proved by agarose gel electrophoresis *** multitargeting gene com-plexes exhibited low cytotoxicity by 3-(4,-dimethylthia-zol-2-yl)-2,5-diphenyltetrazolium bromide *** high internalization efficiency of these gene complexes was confirmed by flow *** results of in vitro transfection demonstrated that these multitargeting gene complexes possessed relatively high transfection *** rapid migration of ECs transfected by these gene complexes was verified by wound healing *** to ECs-targeting ability,cell-penetrating ability and nuclear targeting capacity of REDV-G-TAT-G-NLS pep-tide,the multitargeting polycationic gene carrier with low cytotoxicity and high transfection efficiency has great potential in gene therapy.

关键词： gene carriers multitargeting function ECs transfection efficiency

Synthesis of depsipeptides from L-amino acids and lactones

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Frontiers of Chemical Science and Engineering 2011年第4期5卷 409-415页

作者： Hongfei CAO Yakai FENG Heyun WANG Li ZHANG Musammir KHAN jintang guo School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China Tianjin University-Helmholtz-Zentrum Geesthacht Joint Laboratory for Biomaterials and Regenerative MedicineTianjin 300072ChinaTeltow 14513Germany

By using the corresponding L-amino acid sodium as initiator,ε-caprolactone-depsipeptides CL-Ala and CL-Leu were prepared by the reactions ofε-caprolactone(CL)with L-alanine and L-leucine,respec-tively,and p-dioxanone-depsipeptide(PDO-Leu)was prepared by the reaction of p-dioxanone(PDO)with *** poly(ε-caprolactone)oligomers(PCL-Ala and PCL-Leu)of different molecular weights with depsipeptide unit were synthesized by controlling the feed ratio of L-amino acid sodium and *** presence of the depsipeptide structure in these obtained products was conﬁrmed by 1H NMR spectra and the molecular weight of the poly(ε-caprolactone)oligomers was measured by gel permeation chromatography(GPC).These products con-tain a hydroxyl group and a carboxyl group in one molecule,which means they could act as bifunctional monomers for further polymerization to prepare high molecular weight *** this way,the depsipeptide unit could be introduced into the polymers and the biodegradation rates of the novel polymers could be well controlled in vivo by the tailored molecular structures.

关键词： ε-caprolactone p-dioxanone L-alanine L-leucine depsipeptide

Modification of polycarbonateurethane surface with poly （ethylene glycol） monoacrylate and phosphorylcholine glyceraldehyde for anti-platelet adhesion

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Frontiers of Chemical Science and Engineering 2014年第2期8卷 188-196页

作者： Jing YANG Juan LV Bin GAO Li ZHANG Dazhi YANG Changcan SHI jintang guo Wenzhong LI Yakai FENG School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China Tianjin University-Helmholtz-Zentrum Geesthacht Joint Laboratory for Biomaterials and Regenerative Medicine Tianjin 300072 China Key Laboratory of Systems Bioengineering Ministry of Education Tianjin University Tianjin 300072 China University of Rostock Department of Cardiac Surgery Reference & Translation Center for Cardiac Stem Cell Therapy Schillingallee 69 D-18057 Rostock Germany

Poly（ethylene glycol） monoacrylate （PEGMA） is grafted onto polycarbonateurethane （PCU） surface via ultraviolet initiated photopolymerization. The hydroxyl groups of poly（PEGMA） on the surface react with one NCO group of isophorone diisocyanate （IPD1） and another NCO group of IPDI is then hydrolyzed to form amino terminal group, which is further grafted with phosphorylcholine glyceraldehyde to establish a biocompatible hydrophilic structure on the surface. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy confirm the successful grafting of both PEG and phosphorylcholine functional groups on the surface. The decrease of the water contact angle for the modified film is caused by synergic effect of PEG and phosphorylcholine, which both have the high hydrophilicity. Furthermore, the number of platelets adhered is relative low on the synergetically modified PCU film compared with the PCU film modified only by poly（PEGMA）. Our synergic modification method using both PEG and phosphorylcho- line may be applied in surface modification of bloodcontacting biomaterials and some relevant devices.

关键词： poly(ethylene glycol) monoacrylate phos-phorylcholine polycarbonateurethane surface modifica-tion anti-platelet adhesion biomaterials

Fabrication and characterization of electrospun biocompatible PU/PEGMA hybrid nanofibers by in-situ UV photopolymerization

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Science China(Physics,Mechanics & Astronomy) 2012年第7期55卷 1189-1193页

作者： WANG HeYun FENG YaKai YUAN WenJie ZHAO HaiYang FANG ZiChen KHAN Musammir guo jintang School of Chemical Engineering and Technology Tianjin UniversityTianjin 300072China School of Chemistry and Chemical Engineering Shihezi UniversityShihezi 832003China Key Laboratory of Systems Bioengineering Ministry of EducationTianjin UniversityTianjin 300072China

Poly（ethylene glycol） methacrylate （PEGMA） was introduced into a polyurethane （PU） solution in order to prepare hemocom- patible electrospun membranes for potential application as small diameter vascular scaffolds. Crosslinked PU/PEGMA hybrid nanofibers were fabricated by a reactive electrospinning process with N,N＇-methylenebisacrylamide （MBAm） as erosslinker and benzophenone （BP） as photoinitiator. The photoinduced polymerization and crosslinking reaction took place simultane- ously during the electrospinning process. No significant difference in the membrane morphology was found by SEM when PEGMA content was less than 20 wt%. The crosslinked fibrous membranes of PU/PEGMA exhibit higher hydro- philicity and mechanical strength than PU membrane. These nanofibrous membranes are potential substitutes for artificial vascular scaffolds.

关键词： electrospinning crosslink photopolymerization polyurethane poly(ethylene glycol) methacrylate.