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Preparation of fiber-microsphere scaffolds for loading bioactive substances in gradient amounts

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Chinese Science Bulletin 2013年第27期58卷 3415-3421页

作者： TANG GongWen zhao yunhui YUAN XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin University

Gradient scaffolds are needed for interface tissue regeneration. In this study, a technique combining electrospinning and electrospraying was developed for preparing poly(L-lactide-co-glycolide) (PLGA) fiber-microsphere scaffolds for loading bioactive substances in gradient amounts. The gradient fiber-microsphere scaffolds contain two sheets of electrospun membranes and a sheet of microspheres loaded with bioactive substances in gradient amounts between the electrospun membranes. The morphologies of the gradient scaffolds were characterized and bovine serum albumin (BSA) was loaded as a model bioactive substance. The amount of BSA-loaded microspheres decreased gradually along the length of the gradient scaffold. The addition of poly (ethylene glycol) significantly improved the hydrophilicity of the gradient scaffold and the release behavior of BSA with respect to the gradient became apparent, with differences in the release amounts along the length of the gradient scaffold being observed. The biocompatibility of the gradient scaffold was verified using MC3T3-E1 pre-osteoblastic cells. The study demonstrated that the combination of electrospinning and electrospraying was a feasible method for the preparation of gradient scaffolds for potential applications in interface tissue engineering.

关键词：组织工程支架生物活性物质制备度量加载微纤维白蛋白微球牛血清白蛋白

Self-healing anti-icing coatings prepared from PDMS polyurea

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Science China(Technological Sciences) 2021年第7期64卷 1535-1543页

作者： zhao XueWei PENG Jie GAO ShuHui ZHU KongYing zhao yunhui LI XiaoHui YUAN XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin300350China Analysis and Measurement Center Tianjin UniversityTianjin300072China

With the help of double hydrogen bonds between urea groups, a self-healing anti-icing coating was prepared from polydimethylsiloxane(PDMS)-based polyurea(PDMSPU) that was synthesized from bis(3-aminopropyl)-terminated PDMS and2,4-toluene diisocyanate. Furthermore, by incorporating a lubricant of inert silicone oil and the cross-linking agent of 1,3,5-tris-(4-aminophenoxy)benzene(TAPOB), the anti-icing coatings exhibited elastic, slippery and durable properties. The wettability,ice shear strength, abrasion-resistance, mechanical and self-healing properties of the prepared anti-icing coatings were systematically investigated. Results showed that the ice shear strength of the PDMSPU anti-icing coating with 150 wt% silicone oil was 7.9±2.9 kPa, significantly lower than that of pristine PDMSPU(74.7±7.2 kPa). The additional introduction of 2 wt%TAPOB could effectively counteract the adverse effect of the lubricant so that the tensile strength(~1 MPa) of the coating could be comparable to pristine PDMSPU(855±96 kPa). The PDMSPU coating containing 150 wt% silicone oil and 2 wt% TAPOB could maintain the ice shear strength below 50 kPa against 10 icing/deicing cycles and at 12.0±3.3 kPa after 5000 abrasion cycles, and exhibit self-healing properties after treating at 60°C for 10 or 15 h. The slippery self-healing PDMSPU anti-icing coatings could be suitable for anti-icing surfaces in low temperature environments.

关键词： polydimethylsiloxane polyurea coatings anti-icing self-healing

Ceiling Degree of Polymerization for Brush Polymers Prepared via ROMP of Poly（tert-Butyl Acrylate） Macromonomers

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Chemical Research in Chinese Universities 2018年第5期34卷 828-832页

作者： QIAO Yaping YUAN Xiaoyan zhao yunhui REN Lixia School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Tianjin University Tianjin 300072 P. R. China

Controlled preparation of brush polymers is important in the design of functional materials. In this study, poly（tert-butyl acrylate） macromonomers functionalized with norbornenyl end group（NB-PtBA） were synthesized via atom transfer radical polymerization in three different molecular weights, 2000（NB-PtBA-2k）, 3000（NB-PtBA-3k）, and 8000（NB-PtBA-8k）. Additionally, brush polymers with PtBA as side chains were synthesized via ring-opening metathesis polymerization（ROMP）. Kinetic studies on ROMP of NB-PtBA showed that there was a ceiling degree of polymerization（CDP） for the brush polymers, beyond which the polymerization of NB-PtBA was out of control. For brush polymers of P[NB-PtBA-2k] and P[NB-PtBA-3k], CDPs were estimated to be ca. 400, but the value of P[NB-PtBA-8k] was ca. 100. Therefore, the controlled ROMP of brush polymers was critical at the CDP limit with increased macromonomer molecular weight.

关键词： Ring-opening metathesis polymerization Macromonomer Brush polymer Ceiling degree of polymeriza- tion Kinetics study

Combination of hydrophobically modified γ-poly(glutamic acid)and trehalose achieving high cryosurvival of RBCs

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Science China(Technological Sciences) 2021年第4期64卷 806-816页

作者： ZHANG QiFa LIU Bo CHONG JingHui REN LiXia zhao yunhui YUAN XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China Tianjin Blood Center Tianjin 300110China

Trehalose is expected to be an alternative for toxic glycerol as a biocompatible cryoprotectant of red blood cells(RBCs).In this work,γ-poly(glutamic acid)(PGA)is modified by grafting hydrophobic phenethylamine,3,4-dimethoxyphenylethylamine and dodecylamine,*** graft-modified PGA can significantly enhance cryosurvival of RBCs in combination with *** of dynamic light scattering,hemolysis assay,atomic force microscope and confocal laser scanning microscope suggest that the modified PGA polymers can self-assemble into nanoparticles in phosphate buffer saline solutions at the pH range of 6.0–7.4,and exhibit membrane-disruptive activity due to hydrogen bond,conjugation and hydrophobic interactions with cell *** is assumed that the modified PGA polymers can improve the cryosurvival of RBCs by promoting membrane permeability of *** the three graft-modified polymers,phenethylamine-grafted PGA(PGA-g-PEA)can significantly increase the intracellular trehalose-loading content to 11.3±2.4 m M at pH 7.4,much higher than the value0.17±0.66 m M when trehalose is used without any *** view of the aforementioned merit,the cryosurvival rate of sheep RBCs is increased to about 90%by incubation with 1.0 mg mL-1 PGA-g-PEA and 0.36 M *** vitro cell culture of L929 fibroblasts demonstrates low cytotoxicity of ***,hydrophobic PEA-modified PGA with enhanced intracellular trehalose-loading ability can be potentially applied in glycerol-free RBC cryopreservation or other related biomacromolecule delivery systems.

关键词： γ-poly(glutamic acid) membrane-disruptive activity trehalose cryosurvival red blood cells

Antifogging and antibacterial properties of amphiphilic coatings based on zwitterionic copolymers

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Science China(Technological Sciences) 2021年第4期64卷 817-826页

作者： zhao ChiXu YUAN XiaoYan BAI Shan SUN PingChuan zhao yunhui ZHU KongYing REN LiXia LI XiaoHui School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China Key Laboratory of Functional Polymer Materials of the Ministry of Education and College of Chemistry Nankai UniversityTianjin 300071China Analysis and Measurement Center Tianjin UniversityTianjin 300072China

Tackling fogging and microbial infection problems related to the endoscope lens remain challenges due to visual disturbances and bacterial threats to human ***,highly transparent antifogging and antibacterial coatings were developed in a facile way by thermal curing of zwitterionic copolymers poly(n-butyl methacrylate-co-2-aminoethyl methacrylate-co-sulfobetaine methacrylate)s with 1,3,*** of surface chemical composition and wettability suggested that the copolymer coatings exhibited amphiphilicity with a hydrophobic surface and internal *** prepared amphiphilic coating exhibited excellent antifogging properties both in vivo and in *** introduction of hydrophobic n-butyl methacrylate and cationic aminoethylmethacrylate could improve the stability and antibacterial capability of the *** growth inhibition rates of the coatings against Staphylococcus aureus and Escherichia coli were up to 99%and the copolymer coatings with the zwitterionic groups had low hemolytic rates less than 3%.The amphiphilic copolymer coatings combined antifogging and antibacterial properties may have a promising potential for applications in biomedical devices.

关键词： zwitterionic copolymer amphiphilic coating antifogging antibacterial property hemolysis

Effect of Polyhedral Oligomeric Silsesquioxane and Sorbitol on Properties of Isotactic Polypropylene

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Chemical Research in Chinese Universities 2015年第2期31卷 303-307页

作者： CHEN Guanyun FENG Baixuan ZHU Kongying zhao yunhui YUAN Xiaoyan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Analysis and Measurement Center Tianjin University Tianjin 300072 P. R. China

Isotactic polypropylene（iPP） was modified by the introduction of polyhedral oligomeric silsesquioxanes（POSS） and 1,3：2,4-bis（3,4-dimethylbenzylidene）sorbitol（DMDBS）. Chemical combination of （3-mercapto）- propyl-heptaisobutyl POSS with DMDBS（POSS-DMDBS）, and physical mixing of DMDBS with octaisobutyl POSS （iso-POSS/DMDBS） or trisilanolisobutyl POSS（tri-POSS/DMDBS） were applied respectively to modifying iPP, and the effects of POSS and DMDBS on crystallization, rheological and mechanical properties of iPP were systematically investigated. The results indicate that iso-POSS/DMDBS and tri-POSS/DMDBS were more effective than POSS-DMDBS on the improvement of the crystallization behavior of iPP due to the higher crystallization temperature, while the crystal!inity of iPP containing POSS-DMDBS was enhanced, approximately approached to that of iPP containing tri-POSS/DMDBS. The tensile strength of iPP with POSS-DMDBS was significantly increased from 34 MPa to 40 MPa, as high as that of iPP with iso-POSS/DMDBS. The different effects caused by the specific interaction between POSS and DMDBS could possibly be applied in the modification of iPP.

关键词： Isotactic polypropylene Polyhedral oligomeric silsesquioxane Sorbitol

Efficient Synthesis of Isoquinolines by AgNO3-Catalyzed Sequential Imination-Annulation of 2-Alkynyl Aldehydes with Ammonium Bicarbonate

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Chinese Journal of Chemistry 2016年第9期34卷 857-860页

作者： yunhui zhao Mingjian Luo Yubo Li Xiong Liu Zilong Tang Keqin Deng Gang zhao Hunan Province College Key Laboratory of QSAR/QSPR School of Chemistry and Chemical Engineering Hunan University of Science and Technology Xiangtan Hunan 411201 China Key Laboratory of Synthetic Chemistry of Natural Substances Shanghai Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China Key Laboratory of Theoretical Chemistry and Molecular Simulation Ministry of Education Xiangtan Hunan 411201 China

An operationally simple approach for the tandem synthesis of isoquinolines by the reaction of o-alkynylalde- hydes with ammonium bicarbonate via Ag-catalyzed 6-endo-dig ring closure is described. The reaction conditions and the scope of the reaction are examined, and a variety of substituted isoquinolines are prepared in moderate to excellent yields.

关键词： isoquinolines annulation imination silver nitrate o-alkynyl aldehydes

Enhanced anti-icing properties of branched PDMS coatings with self-regulated surface patterns

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Science China(Technological Sciences) 2020年第6期63卷 960-970页

作者： PENG Jie LIU Bo GAO ShuHui ZHU KongYing zhao yunhui LI Xiao Hui YUAN XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional MaterialsTianjin UniversityTianjin 300350China Analysis and Measurement Center Tianjin UniversityTianjin 300072China

Adverse impact of icing,on either infrastructures or facilities,is the great impulsion for seeking anti-icing coatings with high *** this work,durable icephobic coatings with self-regulated surface patterns were developed from branched polydimethylsiloxane(PDMS)co-crosslinked with fluorinated polyhedral oligomeric silsesquioxane(POSS)through a breath figure *** prepared coatings with patterned microstructures on the surfaces exhibited excellent anti-icing performance ascribed to micro-crack generation between ice and coating surface under a small external *** stable cross-linked network composed of branched PDMS and fluorinated POSS endowed the coatings with durability and abrasion *** ice shear strength was achieved at approximate 19.7±2.5 kPa on coating surface with self-regulated honeycomb *** experiencing 30 icing/deicing cycles,the ice shear strength of the coating varied ***,owing to dedication of fluorinated POSS,the coating showed merely a little increase in ice shear strength after more than 1600 abrasion cycles,which was still in the icephobic range below 50 ***,the prepared coatings with remarkably enhanced anti-icing performance and superior mechanical stability would be promising for the practical applications.

关键词： branched PDMS fluorinated POSS patterned surfaces icephobic coatings durability

Effect of degradation of PLGA and PLGA/β-TCP scaffolds on the growth of osteoblasts

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Chinese Science Bulletin 2011年第10期56卷 982-986页

作者： YANG YanFang TANG GongWen zhao yunhui ZHANG Yang LI XiuLan YUAN XiaoYan School of Materials Science and Engineering Tianjin Key Laboratory of Composite and Functional Materials Tianjin University Tianjin 300072 China Institute of Orthopedics Tianjin Hospital Tianjin 300211 China

Osteoblasts were cultured on porous scaffolds of poly(L-lactide-co-glycolide) (PLGA) and PLGA/β-tricalcium phosphate (β-TCP) to evaluate their *** proliferation of the cells on both scaffolds was examined before and after in vitro degradation for 4,8 and 12 weeks under static (shaking water bath) and dynamic (cyclic loading) *** indicate that porous PLGA and PLGA/β-TCP scaffolds have good biocompatibility and can be used as effective templates for guiding the growth of *** degradation of the scaffolds affects the proliferation of osteoblasts and the cell viability decreased with the degradation time.

关键词： PLGA 多孔支架成骨细胞细胞生长 TCP 退化细胞相容性生物相容性