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 Properties of Gelatin-Chitosan/Montmorillonite Drug-loaded Microspheres

A kind of slow release drug-loaded microspheres were prepared with gelatin, chitosan and montmorillonite（MMT） by an emulsification/chemical cross-linking method using glutaraldehyde as cross-linking agent and acyclovir as model drug. The microspheres were characterized by X-ray diffraction （XRD）, Fourier transform infrared （FT-IR） and scanning electron microscopy （SEM）, respectively. The morphology, drug content, encapsulation efficiency and drug-release behavior were investigated with different MMT contents. The experimental results indicated that intercalated microspheres could be prepared, the morphology of microspheres was markedly affected by MMT. The glomeration performance of uncross-linked microspheres was improved because of the physical cross-linking of MMT. Drug content and encapsulation efficiency were decreased when increased the content of MMT, but burst release and the drug release were significantly decreased with the addition of MMT. Effective physical cross-linking could be formed when added MMT, and MMT could reduce the content of toxic chemical cross-linking agents.

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.

Effect of chitosan/type I collagen/gelatin composites in biocompatibility and nerve repair

Chitosan, collagen I and gelatin were mixed in appropriate quantities to develop a new nerve repair material, with good arrangement and structure, as well as even aperture size. The composite material was sterilized by 60Co irradiation for 24 hours prior to implantation in the right thigh of rats following sciatic nerve damage. Results showed that the material was nontoxic to the kidneys and the liver, and did not induce an inflammatory response in the muscles. The composite material enhanced the recovery of sciatic nerve damage in rats. These experimental findings indicate that the composite material offers good biocompatibility and has a positive effect on injured nerve rehabilitation.

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.

Adsorption and Desorption Behaviors of Bovine Serum Albumin on Gelatin/Chitosan Sponge

Gelatin (Gel) and chitosan (CTS) have several biomedical applications because of their biodegradability and biocompatibility. Crosslinking of Gel and Gel/CTS systems was evaluated using N-acetyl-D-glucosamine (GlcNAc) formed into sponges by lyophilization. The prepared sponges were used to study the adsorption and desorption of fluorescein isothiocyanate (FITC) labeled bovine serum albumin (BSA) as a model instead of a growth factor. The effect of FITC-BSA concentration and temperature on the adsorption behavior of Gel/CTS sponges was investigated. The Langmuir adsorption isotherm model was used on the basis of the assumption that monolayer adsorption occurs on the surface;the results fit with the experiment data. The adsorption constants were 5.77 and 9.68 mL/mg for Gel and Gel/CTS sponges, respectively. The adsorption thermodynamic constants were found;adsorption onto sponges was an exothermic reaction. In particular, Gibbs free energy (ΔG) exhibited negative values in the range of 283 - 343 K for both Gel and Gel/CTS sponges, demonstrating the spontaneous nature of adsorption reaction. In addition, desorption behavior was evaluated for different concentrations and pH values of the FITC-BSA solution. The high adsorbed amounts of FITC-BSA on sponge resulted in high desorbed amounts in sponge, up to 55% from 3.5 mg/mL adsorbed concentration (around 1.5 mg from 3 mg adsorb amount). Desorption decreased following the buffer solution pH decrease, from 7.4 to 4 and 2 in Gel and Gel/CTS sponges, respectively. Based on the results of this preliminary study, these composite sponges could have significant application in biomedical materials.

Preparation and Characterization of Composite Drug Membranes of Gelatin/Chitosan to Ocular

Composite drug membranes of gelatin/chitosan for therapy of glaucoma by trabeculectomy were prepared through solvent volatilization, using triamcinolone acetonide as a model drug. The membranes were characterized try FT-IR, X-RD and SEM. Their degradability and swelling ability and biocompatibilhy were studied. The results showed that biocompatibilhy, flexibility, swelling ability and degradabilhy of the composhe films were better than pure film of chitosan. The composite membrane containing 25% （ w/ w ） of gelatin was best. The drug was loaded in fdm in crystallite. The rabbit eyes experiment after 8 weeks should that the form of follicle was all right, and ophthalmotonus maintain in the pesfect level.

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。

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。

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。

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。

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。

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。