Blend Films of Chitosan-Gelatin

Chitosan\|gelatin blend films were prepared successfully by solution method, and characterized by FT\|IR, X\|ray diffraction, SEM, optical transmittance, percent water absorption and measurements of mechanical properties. The results indicated there was some strong interaction and good compatibility between chitosan and gelatin molecule in the blend films. The introduction of chitosan was beneficial to decrease the percent water absorption,improve mechanical properties of gelatin. \;

Preparation and Characterization in vitro of Sustained-release Captopril/ Chitosan-gelatin Net-polymer Microspheres(Cap/CGNPMs)

The captopril/ Chitosan-gelatin net-polymer microspheres （ Gap/ CGNPMs ） were prepared using Chitosan （ CS ） and gelatin （ Gel ） by the methods of emulsification. A cross linked reagent alone or in combination with microcrystalline cellulose （ MCC ） was added in the process of preparation of microspheres to eliminate dose dumping and burst phenomenon of microspheres for the improvemeat of the therapeutic efficiency and the decrease of the side effects of captopril （ Cap ）. The results indicate that Cap/ CGNPMs have a spherical shape , smooth surface roorphology and integral inside structure and no adhesive phenomena and good roobility , and the size distribution is mairdy from 220 to 280 μm. Researches on the Cap release test in vitro demonstrate that Cap/ CGNPMs are of the role of retarding release of Cap compared with Cap ordinary tablets （COT）, embedding ratio （ER） , drug loading （ DL ）, and swelling ratio （ SR ）, and release behaviors of CGNPMS are influenced by process conditions of preparation such as experimental material ratio （EMR） , composition of cross linking reagents. Among these factors , the EMR（1/4）, CLR （ FOR ＋ TPP） and 0.75% microcrystulline cellulose （MCC） added to the microspheres are the optimal scheme to the preparation of Cap/CGNPMs. The Cap/CGNPMs have a good characteristic of sustained release of drug, and the process of emulsifieation and crossinking process is simple and stable. The CGNPMs is probable to be one of an ideal sustained release system for water-soluble drugs.

Swelling Studies of Chitosan-Gelatin Films Cross-Linked by Sulfate

Swelling properties of chitosan-gelatin films cross-linked by sulfate were investigated. Sulfate cross-linked chitosan-gelatin films (SCG) were prepared simply by dipping chitosan-gelatin films into sodium sulfate solution. The swelling behavior of SCG was investigated as a function of pH and ionic strength. Under acidic conditions pH less than 4, SCG swelled less than 120%, while under the conditions pH larger than 7.4, SCG swelled very significantly, the swelling ratio was over 350%. Sodium chloride weakened the electrostatic interaction between sulfate and amine ions of chitosan and gelatin, therefore facilitated the film swelling. The swelling ratio increased with increasing sodium chloride concentration, the SCG dissociated in the sodium chloride concentration of 0.20 mol·L?1. The parameters of film preparation such as sulfate concentration, dipping time, sulfate solution pH, influenced the film swelling behavior. The lower concentration and the higher pH of sulfate solution resulted in a larger swelling ratio. Key words chitosan - gelatin - sulfate cross-linking - swelling CLC number O 636.1 Foundation item: Supported by the National Natural Science Foundation of China (29977014)Biography: Xiao Ling (1964-), female, Associate professor, research direction, biopolymers.

Biocompatibility Studies on Bone Marrow Stromal Cells with Chitosan-gelatin Blends

To study the effect of chitosan-gelatin blends on the growth and proliferation of in vitro cultured bone marrow stromal cells(BMSCs) and explore a new carrier for the application of tissure engineering, cells from long bones of young rabbitsaged less than two weeks were expanded in vitro for one week and seeded onto the surface of pure chitosan and chitosan-gelatin blends. Cells attached to and proliferated on both pure chitosan and chitosan-gelatin blends were monitored with the aid of an inverted light microscope and a scanning electron microscope. The cell viability was monitored by MTT after 2, 4, 6, 8 days seeding. BMSCs could be attached to and proliferated on both pure chitosan and chitosan-gelatin blends and remain their morphologies seen in vivo. Chitosan-gelatin blends could promote BMSCs to proliferate(P<0.01). It is confirmed that chitosan-gelatin blends maintain the bioactivity feature of chitosan and even enhance the growth and proliferation of in vitro cultured BMSCs because of the adding of gelatin. It is a potential carrier for the delivery of cells tissue engineering.

含ε-聚赖氨酸的壳聚糖/明胶涂层对海参的保鲜作用

海参具有水分含量高、蛋白含量高的原料特性,在储运过程中极易发生腐败。该文研究含ε-聚赖氨酸(ε-polylysine,ε-PL)的壳聚糖(chitosan,CS)/明胶(gelatin,Gel)涂层对海参冷藏过程中品质劣化的延缓作用。结果表明,未涂层的空白组海参在贮藏第3天已经腐败,菌落总数及总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量快速上升。CS-Gel/ε-PL涂层能够有效抑制海参上微生物的生长,贮藏7 d时,处理组菌落总数为4.07 lg(CFU/mL),TVB-N含量仅为28.42 mg/100 g,仍低于安全限值。另外,CS-Gel/ε-PL涂层处理组海参在贮藏过程中持水率高,氮氧化合物、甲烷等短链烷烃、无机硫化物以及有机硫化物等腐败不良气味产生量低,硬度、弹性及咀嚼性等质构特性保持良好。通过感官评价分析,发现CS-Gel/ε-PL涂层可有效延缓贮藏过程中海参体壁暗淡、特征鲜味消失、组织状态松散、弹性下降等现象。以上表明CS-Gel/ε-PL对即食海参具有良好保鲜效果。

Compatibility of Chitosan-Gelatin Films with Adipose Tissue Derived Stromal Cells

Chitosan has been shown to be a promising material for various applications in tissue engineering. Recently, adipose tissue derived stromal cells （ADSCs） have been investigated as an alternative source of seed cells for tissue engineering. The compatibility of chitosan and chitosan-gelatin complexes with ADSCs is not known. In the present study, ADSCs were isolated and characterized by phenotype using fluorescence-activated cell sorting （FACS）. The morphology, viability, and the ability of the ADSCs to differentiate on chitosan and chitosan-gelatin composite films with 60 wt.% gelatin were evaluated. Results show that the ADSCs are positive for CD29, CD44, and CD105, but negative for CD31, CD34, and CD45. ADSCs adhere and grow better on the composite films than on the chitosan films. The ability of ADSCs to differentiate into osteogenic and adipogenic lineage cells is not affected by their being cultured on chitosan-gelatin composite films. Therefore, chitosan-gelatin composite films are compatible with ADSCs and do not impair the ability of ADSCs to differentiate into osteogenic and adipogenic lineage cells.

Effects of hyaluronic acid-chitosan-gelatin complex on the apoptosis and cell cycle of L929 cells

With the development in the field of tissue en-gineering, the interaction between biomaterials and cells has been deeply studied. Viewing the cells seeded on the surface of materials as an organic whole, cell cycle and apoptosis are analyzed to deepen the study of cell compatibility on bioma-terials, while cell proliferation and differentiation are stud-ied at the same time. In this paper, hyaluronic acid is incor-porated into the chitosan-gelatin system. Propidium iodide(PI) was used in cell cycle analysis and the double-staining of cells with annexin-V and PI was applied in cell apoptosisanalysis. The results show that incorporated hyaluronic acid shortens the adaptation period of cells on the material sur-face, and then cells enter the normal cell cycle quickly. Inaddition, added hyaluronic acid inhibits cell apoptosis trig-gered by the membranes. Therefore, hyaluronic acid im-proves the cell compatibility of chitosan-gelatin system andbenefits the design of biomimetic materials.

丝素蛋白/明胶/壳聚糖三维多孔软骨组织支架的制备及体外评价

背景:软骨缺损是骨科医生面临的主要临床挑战之一,组织工程是一种结合了工程学和细胞生物学知识的跨学科方法,为软骨缺损的修复提供了新思路与途径。目的:基于丝素蛋白、明胶和壳聚糖制备多组分复合支架,通过评估其理化性质和生物学性能,筛选能够适合软骨再生的三维多孔支架。方法:以丝素蛋白、明胶和壳聚糖为基础材料,通过真空冷冻干燥法制备4组多孔支架,分别为明胶/壳聚糖支架、丝素蛋白/壳聚糖支架、丝素蛋白/明胶支架和丝素蛋白/明胶/壳聚糖支架,通过扫描电镜、X射线衍射、孔隙率、吸水膨胀率和生物降解率及力学性能等检测筛选出合适的软骨支架。然后将软骨支架与骨关节炎患者软骨细胞共培养,通过细胞黏附率、活死染色和增殖活性等检测体外评估多孔支架用于软骨损伤修复的可行性。结果与结论:①4组支架均具有多孔结构,综合物理性能检测结果得出丝素蛋白/明胶/壳聚糖支架更符合软骨缺损修复的要求,该支架的孔径为(176.00±53.68)μm,孔隙率为(80.15±2.57)%,吸水溶胀率为(3712±358)%,体外浸泡于含溶菌酶的PBS中28 d后的生物降解速率为(46.87±3.25)%,且具有良好的机械性能;②软骨细胞可在丝素蛋白/明胶/壳聚糖支架上良好黏附,且随着时间的延长,细胞黏附率增加;CCK8和活/死细胞双染检测结果显示,丝素蛋白/明胶/壳聚糖支架具有良好的生物相容性和较低的细胞毒性;③结果表明,丝素蛋白/明胶/壳聚糖支架具有高度水合3D结构、合适的孔径和孔隙率、良好的生物降解性能和优越的机械性能,可以为营养物质的转运和软骨细胞的附着、增殖提供良好的网状骨架和微环境。

壳聚糖/明胶/植酸复合阻燃涂料的制备及性能

【目的】为提高木材的阻燃性能,扩展生物基阻燃材料在木材中的应用,制备壳聚糖/明胶/植酸全生物基可膨胀复合阻燃涂料,并且探索其在木材上的应用性能。【方法】以壳聚糖和明胶为成膜物质,水为溶剂,按照壳聚糖、明胶和植酸质量比3∶2∶(0~1.5)制备可膨胀复合阻燃涂料;将其涂覆于木材表面后制备木材的阻燃涂层(CGPx)。利用扫描电子显微镜和傅里叶变换红外光谱观察涂层的形貌结构以及元素分布;使用铅笔硬度仪和附着力检测评估涂层的硬度以及附着力;采用热重测试、可燃耐火测试和锥形量热测试综合评估处理材的热稳定性和阻燃性能;最后采用扫描电子显微镜和傅里叶变换红外光谱分析残炭的形貌结构和元素分布,并分析阻燃机理。【结果】CGPx在木材上表现出优良的附着力和硬度,其中CGP1.5组附着力等级达到1级,铅笔硬度达到7H。CGPx木材表现出优良的热稳定性,其中CGP1.5组残炭率达到44.2%。在可燃耐火测试中,CGPx木材表现出优异的耐火性能。在锥形量热测试中,CGP1.5组热释放速率峰值下降了34.3%,速率峰值出现时间推迟至284 s,总热释放量下降了15.5%,CO和CO_(2)释放速率也有所降低,同时火灾指数为0.189,火焰增长指数为0.708。木材的阻燃性能得到增强。【结论】使用全生物基阻燃涂料涂覆木材的处理方法,有效提高了木材的热稳定性与阻燃性能,丰富了绿色可持续的木材阻燃体系。

阳离子型苯丙乳液施胶剂的改性及物性研究

为改善阳离子型苯丙乳液施胶剂的环保性,采用来源广泛、成膜性好且易生物降解的明胶和壳聚糖进行复合改性,确定了壳聚糖用量为阳离子型苯丙乳液施胶剂质量的0.35%,明胶用量应不高于0.35%,重点研究了明胶用量对明胶-壳聚糖改性阳离子型苯丙乳液施胶剂的分散性、pH、表面张力和固含量等物性的影响,结果表明:随着明胶用量的逐渐增加,明胶-壳聚糖改性阳离子型苯丙乳液施胶剂的静置稳定性、离心稳定性高,分散性为一级,pH保持2.30不变,固含量变化大,而表面张力和纸张白度变化小。

改性鸡肺、牛肺、猪肺明胶/羧甲基壳聚糖复合水凝胶的制备及性能

为提高畜禽养殖效益、实现高附加值的畜禽肺资源化利用,本研究以鸡肺、牛肺、猪肺及与羧甲基壳聚糖为原料,在鸡肺、牛肺、猪肺明胶制备及改性的基础上,将羧甲基壳聚糖分别与改性鸡肺、牛肺、猪肺明胶按1∶1、1∶2和2∶1体积比进行交联反应制备复合水凝胶,并进一步对复合水凝胶的关联度、凝胶强度、红外光谱、溶胀性、热变特征、微观结构及失水率等理化性质进行分析。结果表明,当羧甲基壳聚糖分别与改性鸡肺、牛肺、猪肺明胶按1∶2体积比时,配制得到的复合水凝胶性质最好。其中,羧甲基壳聚糖与改性牛肺明胶按1∶2体积比配制得到的复合水凝胶交联度、凝胶强度、孔隙率和失水率分别为45.4%、5.24 N、64.58%和87.6%,优于羧甲基壳聚糖分别与改性鸡肺明胶、改性猪肺明胶按1∶2体积比配制得到的复合水凝胶。本研究结果为畜禽肺的高附加值资源化利用提供了新思路。

水凝胶黏合剂用于止血的研究进展

不可控制的出血通常会导致患者病死率升高,止血海绵、纱布和绷带作为传统的止血产品被广泛使用。然而,传统的止血装置或止血剂已不能满足治疗大出血的需要。水凝胶黏合剂作为近年来新兴的组织黏合剂在止血方面具有很大的应用潜力,具有黏附性的聚合物水凝胶相关研究迅速发展。本文介绍国内外水凝胶黏合剂用于止血的最新研究进展及未来的发展趋势,以期为进一步的临床研究提供新思路。

鱼明胶基可食抗菌膜的制备及性能研究

为提高鱼明胶可食膜的抑菌性能和机械性能。采用流延成膜,以明胶-海藻酸钠为基底,掺入羧化壳聚糖制备三元共混。评价复合膜的机械性能、水蒸气透过性、透光率、抑菌性能和傅里叶变换红外光谱等指标,探究不同添加量羧化壳聚糖对复合膜性能的影响。结果表明,复合膜各组分之间存在较强的相互作用。羧化壳聚糖的添加可以有效改善复合膜的抗拉强度和阻水性,提高复合膜的紫外阻隔性能和抑菌活性。其中,羧化壳聚糖添加量为10 g/L制成的复合膜,其抗拉强度为(7.06±0.15)MPa、断裂伸长率为(101.26±0.67)%、水蒸气透过率为(0.94±0.01)g·mm/(m^(2)·h·kPa)、抑菌活性为(37.62±10.27)%,可作为食品内包装材料。

壳聚糖/明胶复合微球的制备及吸附性能研究

以壳聚糖和明胶为原料,span 80为乳化剂,戊二醛为交联剂,采用乳化交联法制备了壳聚糖/明胶复合微球并用于Cr(Ⅵ)的吸附。考察了复合微球的各制备因素对微球形貌的影响,通过单因素分析研究了壳聚糖与明胶的比例、乳化剂用量、乳化时间对复合微球吸附性能的影响。结果表明,壳聚糖与明胶的比例为1∶2、span 80用量为6mL、乳化时间为50min时,制备的复合微球对Cr(Ⅵ)的吸附性能良好,吸附量较大,Cr(Ⅵ)的去除率可达95.3%。

以壳聚糖和明胶为复合生物墨水3D打印的脊髓仿生支架及其生物相容性研究

目的:探究3D打印脊髓仿生支架的复合生物墨水配方及生物相容性和可靠性评估。方法:利用3D打印技术,以壳聚糖(chitosan,C)和明胶(gelatin,G)为基础复合生物墨水,比较不同配比复合生物墨水的理化性能:孔隙率、溶胀率、流变性能、降解速率、力学性能分析。通过优化打印参数,打印出特定空间构型的脊髓外形仿生支架。接着运用仿生支架材料浸提液与SH-SY5Y细胞共培养方法,通过扫描电子显微镜和CCK-8实验评估该支架材料的细胞毒性及其对细胞增殖能力的影响。结果:通过比较最终选择4%浓度的C和6%浓度G(4C6G)组为最适的复合生物墨水配方并进行后续的研究。在打印速度1.5 mm/s、压强0.09~0.11 MPa、层厚0.1 mm、间距1 mm、针头0.11 mm的参数下,可以实现打印出5 mm×5 mm×0.9 mm尺寸的蝴蝶形状高保真度的脊髓仿生支架。扫描电子显微镜可见SH-SY5Y细胞黏附在支架内部,并且能正常生长;CCK-8结果显示,浸提液无细胞毒性。结论:以C和G为复合生物墨水有望成为脊髓损伤修复仿生支架的原材料。

壳聚糖自组装颗粒与明胶-大豆分离蛋白微胶束协同构建高内相乳液体系

为了提升高内相乳液(high internal phase emulsions,HIPEs)的结构强度及稳定性,以满足3D打印油墨和脂肪代替物的实际需求,本研究以明胶-大豆分离蛋白复合微胶束作为乳化剂,同时引入不同质量分数的壳聚糖(chitosan,CS)自组装纳米颗粒以提高HIPEs的自支撑性及其稳定性。结果表明,随着CS添加量的增加,HIPEs呈现出更佳的自支撑性能、更高的黏弹性,以及更小、更致密的微观结构。经3D打印后样品未出现塌陷。此外,在不同盐离子浓度(0~500 mmol/L)和pH值(5.0~7.5)条件下,HIPEs仍保持良好稳定性。本研究结果可为个性化定制营养食品,以及低脂健康肉制品的开发提供新思路。

亚硫酸钠-壳聚糖微粒对明胶膜结构和性能的影响

本研究以明胶为成膜基质,添加亚硫酸钠-壳聚糖微粒制备亚硫酸钠-壳聚糖微粒/复合明胶膜,探究亚硫酸钠-壳聚糖微粒对明胶膜结构和性能的影响。对明胶膜进行厚度、水合性能、阻隔性能、力学性能、光学性能、热稳定性和抗氧化性的测定,并对其进行结构表征。结果表明,添加亚硫酸钠-壳聚糖微粒的明胶膜厚度显著降低(P<0.05)、溶胀率显著提高(P<0.05)、溶蚀率从79.41%降低至18.21%、抗拉强度由79.10 MPa提高至128.96 MPa、不透明度由3.75提高至6.77、热稳定性提高以及DPPH自由基清除率由14.41%提高至65.05%,而膜的水蒸气透过率和断裂伸长率未发生明显变化。此外,亚硫酸钠-壳聚糖微粒与明胶分子之间具有较高的相容性,亚硫酸钠-壳聚糖微粒的加入改变了明胶膜的结构。综上所述,亚硫酸钠-壳聚糖微粒的加入能够在一定程度上改变明胶膜的结构、提高明胶膜的性能。本研究为抗氧化复合明胶膜的制备和应用提供一定的理论指导和数据参考。

壳寡糖交联明胶可生物降解薄膜的制备与性能研究

目的:研究壳寡糖改性对明胶基薄膜性能的影响。方法:以废猪皮中提取明胶为基质,以壳寡糖和聚乙烯醇为改性交联剂,制备得到了明胶基薄膜。利用红外光谱、X射线衍射、扫描电子显微镜、分光光度法、拉力试验测试法对其结构和力学性能进行了测定,并测试了明胶基薄膜在抗氧化、抗菌、水稳定性和生物降解方面的性能。结果:交联改性后明胶薄膜的力学性能得到显著提升,断裂应力最高可达37.09 MPa,最大撕裂能为56.71 kJ/m^(2),且浸泡于水中48 h仍能维持良好的物理形态,此外,薄膜还拥有优异透光性(最大可达92.32%),良好抗氧化性(自由基的清除率最高可达75.12%),优异抗菌性和生物降解性(完全降解时间<45 h)。结论:壳寡糖改性一定程度上改善了明胶基薄膜的力学性能和生物降解性能,赋予了薄膜良好抗菌性和抗氧化能力,表明其在食品包装上存在较大潜在应用价值。

食品保鲜树脂的合成与性能研究进展

食品保鲜树脂的合成方法主要有溶液浇注法、凝胶浇注法、流延法、溶液共混法、喷雾干燥法等。以壳聚糖、魔芋葡甘露聚糖、海藻酸钠和明胶这4种物质为基材,分别对其与不同物质复合产生的抗真菌和细菌性能以及保鲜性能的应用研究进行了综述,并对4种保鲜树脂的发展方向进行了展望。

古籍墨迹修复加固材料的性能效果研究

外部环境及条件(如潮湿、光照、虫害等)对古籍的作用,不仅会影响纸张,还会使得其上的墨迹发生改变(如洇墨、掉墨等)。同时,古籍修复中常使用水等溶剂或药剂进行清洁、漂洗等处理,亦可能导致墨迹的脱落、洇化。因此,如何对古籍等纸质文物进行固色保护是纸质文物保护研究的重要问题之一。鉴于此,本工作以羧甲基纤维素、胶矾水及壳聚糖季铵盐为固色材料,通过色度测量、pH值测定、扫描电子显微镜-能谱(SEM-EDX)分析、傅里叶变换红外光谱(FTIR)分析、接触角测量、固色试验及力学性能测试等手段,先后从固色材料对纸张性质的影响、字迹的固色效果及纸和颜料间的相互作用、固色材料适用性及其拓展效果三方面展开研究。结果显示,羧甲基纤维素、胶矾水及壳聚糖季铵盐三种固色材料都具有一定的固色效果,但其性能各异。因此,本工作从多方面综合比较了这三种固色材料对墨及红、蓝墨水的固色效果和性能的差异性,为古籍修复固色材料的选择和评价方法提供基础和借鉴。