响应面优化明胶-壳聚糖可食性复合膜的制备

目的制备明胶-壳聚糖可食性复合膜,以期为不同的实际应用提供实验数据和理论依据。方法利用明胶和壳聚糖的分子结构特点以及聚乙二醇400(PEG-400)等添加物质的性能构效关系,采用溶液浇注法制得明胶-壳聚糖复合膜,研究明胶-壳聚糖的质量分数、明胶与壳聚糖的质量比、PEG-400质量分数对复合膜性能的影响,并根据Box-Benhnke中心组合设计原理设计响应面分析试验,探讨各因素之间的交互作用,探索出明胶-壳聚糖膜的最佳工艺配方。结果膜的物理性能受明胶-壳聚糖质量分数、明胶与壳聚糖的质量比、PEG-400质量分数以及两两交互之间的影响较大。当明胶-壳聚糖的质量分数为8.5%,明胶与壳聚糖的质量比为7∶3,PEG-400质量分数为10%时,膜的拉伸强度为19.53 MPa,断裂伸长率为39.82%。结论所制作膜的透明度、光泽度、表面光滑度、气味及物理性能等各项表征均为良好。     

硬脂酸对可食性膜材料性能的影响研究

为改善壳聚糖-明胶膜材料的性能,将硬脂酸加入到壳聚糖-明胶铸膜液中,制备一系列不同硬脂酸含量的三元共混膜。对其力学性能、阻氧性、阻油性、水蒸汽透过系数和透光率进行深入研究,并将其性能与壳聚糖单一膜、壳聚糖-明胶二元膜进行对比。结果表明:硬脂酸的加入对共混膜的各方面性能均产生了影响,且当壳聚糖∶硬脂酸=4∶1时,膜的各方面性能均处于最佳状态。其力学性能、阻氧性、透油系数及透光性较壳聚糖-明胶膜、壳聚糖膜差异并不显著,而其水蒸汽透过系数却得到显著的改善,为3.25E-8g·cm/(cm2·s·Pa)。     

明胶-壳聚糖复合膜的制备与性能

制备了一系列不同配比的明胶-壳聚糖复合膜,研究了壳聚糖含量对复合膜力学性能、吸湿性能的影响,通过X射线衍射和红外光谱分析了复合膜的结构。结果表明,复合膜及纯壳聚糖膜的断裂伸长率和拉伸强度均大于纯明胶膜,壳聚糖的加入可改善膜的力学性能。随壳聚糖含量的增加,复合膜的吸湿率增大。明胶与壳聚糖分子间存在较强的相互作用,与明胶共...     

羟丙基纤维素/壳聚糖共混膜的制备与性能

采用溶液共混法制备了一系列不同比例的羟丙基纤维素(HPC)/壳聚糖(CS)共混膜,研究了羟丙基纤维素含量对共混膜的力学性能、吸湿性能、透光性能等的影响。结果表明,HPC/CS共混膜的断裂伸长率随着HPC含量的增加而增加,而拉伸强度则先提高后下降,且在含量为40%时共混膜的拉伸强度达到最大;共混膜在可见光区300nm~800nm的最大透光率均大于70%;随着HPC含量的增加共混膜的吸水率大大降低。     

明胶-甘油-酪蛋白酸钠原位组装复合膜及分析EI北大核心CSCD

首先将牛奶中提取的酪蛋白在温度为95℃、0.5mol/L的NaOH溶液中水解3h,然后同甘油和明胶进行组装制膜。研究了甘油和明胶添加量对所制复合膜的拉伸强度和断裂伸长率以及阻水和阻氧性能的影响,并根据成膜组分的分子结构和作用特性,分析了成膜机理。结果表明,甘油和明胶的加入能显著提高复合膜的力学性能,改善膜的阻水和阻氧能力。当甘油、明胶和酪蛋白质量比为0.16∶0.80∶1.0时,膜的拉伸强度、水蒸气透过率和过氧化值分别为58.11MPa、4.44×10-6g/(m·h·Pa)和-7.52 meq/kg。明胶中氨基和羧基的存在同甘油的羟基和酪蛋白中的氨基和羧基之间的次级键作用是协同成膜的主要原因。     

壳聚糖-葡甘聚糖共混改性的研究

对壳聚糖-葡甘聚糖共混改性进行了研究,并对共混膜的力学性能、透气性、透过率进行一系列的性能测试.实验结果表明:壳聚糖与葡甘聚糖在共混膜中存在强烈的相互作用及良好的相容性;共混膜的力学性能随葡甘聚糖含量的增加而得到明显提高,当壳聚糖/葡甘聚糖的体积比为7/3,甘油添加量为15%(质量分数,后同)时,共混膜的各项性能达到最优.     

壳聚糖/聚乳酸/聚羟基丁酸酯人工硬脑膜的制备与性能研究

以壳聚糖、聚乳酸、聚(R)-3-羟基丁酸甲酯等为主要成膜物质,用流延法制得新型薄膜材料。研究表明,当壳聚糖∶明胶∶聚乳酸为1∶1∶1时,得到膜的抗拉强度比其他的可生物降解膜都大,达到27.346MPa;当壳聚糖∶明胶∶聚(R)-3-羟基丁酸甲酯为1∶1∶1时,其抗拉强度达到24.363Mpa,防漏性能达到80h。经模拟体内降解研究,在人工脑脊液的环境中浸置44d后,降解率分别为20%左右,降解速度较慢,可以保持其结构6～7周,有利于引导组织再生材料的基本要求。因此该复合膜有望成为医用可生物降解人工硬脑膜。     

醋酸纤维素-壳聚糖共混膜的制备及性能研究

以乙酸为溶剂制备了壳聚糖(CS)含量不同的醋酸纤维素-壳聚糖(CA-CS)共混膜.通过对共混膜溶胀度、拉伸强度、酸碱使用范围、分离性能的测试,发现随着壳聚糖含量的增加,膜在水中的溶胀度上升,膜的拉伸强度下降,膜的酸碱使用范围变宽.当聚合物浓度为18%、共混物壳聚糖含量为30%、溶剂乙酸水溶液的浓度为50%时,制备的共混膜的分离效果最好,性能也比较稳定.     

仿贝壳结构壳聚糖/绢云母复合薄膜的制备和性能

采用物理共混的简易方法制备了壳聚糖/绢云母复合薄膜。场发射扫描电镜观测的结果表明,这种薄膜具有明显的取向"砖-泥"仿贝壳结构。这种独特仿生结构的形成显著地提高了壳聚糖复合薄膜的力学性能(拉伸强度和断裂伸长率),并且保持了优异的柔软弯曲性能。同时,这种复合薄膜具有良好的透明性和电绝缘性能。     

PHA/PLA生物降解共混膜的制备

采用共混改性方法,将聚乳酸添加到聚羟基脂肪酸酯中,以提高材料的力学性能和成膜性能,制备了生物降解膜。通过对原材料进行黏度测试,确定共混加工工艺的加工温度为200℃,转速为20 r/min时,共混效果较好。对共混膜进行了力学性能测试和断面结构分析,得到当PHA与PLA质量比为100∶50时,膜的拉伸强度为30 MPa,断裂伸长率为100%,共混膜的整体性能较佳。土埋降解实验显示共混膜具有一定的降解性能。     

Implantable biodegradable sponges: effect of interpolymer complex formation of chitosan with gelatin on the release behavior of tramadol hydrochloride

The effect of interpolymer complex formation between positively charged chitosan and negatively charged gelatin (Type B) on the release behavior of tramadol hydrochloride from biodegradable chitosan-gelatin sponges was studied. Mixed sponges were prepared by freeze-drying the cross-linked homogenous stable foams produced from chitosan and gelatin solutions where gelatin acts as a foam builder. Generation of stable foams was optimized where concentration, pH of gelatin solution, temperature, speed and duration of whipping process, and, chitosan-gelatin ratio drastically affect the properties and the stability of the produced foams. The prepared sponges were evaluated for their morphology, drug content, and microstructure using scanning electron microscopy, mechanical properties, uptake capacity, drug release profile, and their pharmacodynamic activity in terms of the analgesic effect after implantation in Wistar rats.

It was revealed that whipping 7% (w/w) gelatin solution, of pH 5.5, for 15 min at 25°C with a stirring speed of 1000 rpm was the optimum conditions for stable gelatin foam generation. Moreover, homogenous, uniform chitosan-gelatin foam with small air bubbles were produced by mixing 2.5% w/w chitosan solution with 7% w/w gelatinsolution in 1:5 ratio. Indeed, polyionic complexation between chitosan and gelatin overcame the drawbacks of chitosan sponge mechanical properties where, pliable, soft, and compressible sponge with high fluid uptake capacity was produced at 25°Cand 65% relative humidity without any added plasticizer. Drugreleasestudies showed a successful retardation of the incorporated drug where the t_50% values of the dissolution profiles were 0.55, 3.03, and 4.73 hr for cross-linked gelatin, un-cross-linked chitosan-gelatin, and cross-linked chitosan-gelatin sponges, respectively. All the release experiments followed Higuchi's diffusion mechanism over 12 hr. The achieved drug prolongation was a result of a combined effect of both cross-linking and polyelectrolyte complexation between chitosan and gelatin. The analgesic activity of the implanted tramadol hydrochloride mixed chitosan-gelatin sponge showed reasonable analgesic effect that was maintained for more than 8 hr. Therefore, the use of chitosan and gelatin together appears to allow the formulator to manipulate both the drug release profiles and the mechanical properties of the sponge that could be effectively implanted.     

Studied on a novel human keratinocyte membrane delivery system in vitro

The culture of keratinocytes on flexible membranes has been proposed as a means to simplify, accelerate and improve the efficiency with which proliferating cells are delivered to full thickness or non-healing skin defects. The purpose of this article was to study the ability of chitosan-gelatin manbranes to facilitate the growth of human keratinocytes. The membranes with different chitosan contents were studied. The surface properties of chitosan-gelatin membranes were investigate by SEM, and water contact angle test. The mechanical property of the membranes was tested. Data implied that gelatin could make the membranes more flexible and hydrophilic than chitosan membranes, which may regulate the seeded cells behavior. Loading human keratinocytes on chitosan-gelatin membranes, cells attachment, spread, and growth were investigated by light microscopy, SEM, and MTT test. The results suggested that the adhesion and proliferation of keratinocytes seeded on chitosan-gelatin membranes were same as on tissue culture plate, in which gelatin could modify the interaction between keratinocytes and chitosan membranes. Therefore, chitosan-gelatin membrane is a good candidate for keratinocytes delivery system.     

Preparation and bioactivity evaluation of hydroxyapatite-titania/chitosan-gelatin polymeric biocomposites

Biocomposites consisting of hydroxyapatite (HA) and natural polymers such as collagen, chitosan, chitin,and gelatin have been extensively investigated. However, studies on the combination of HA and titania with chitosan and gelatin have not been conducted yet. Novel biodegradable hydroxyapatite-titania/chitosan-gelatin polymeric composites were fabricated. In this work, our results are concerning with the preparation and characterization of HA powder and HA filler containing titania powder (10 and 30%) with a chitosan and gelatin copolymer matrix. The present research focuses on characterizing the structure of this novel class of biocomposites. Thermogravimetric analysis (TGA), X-ray diffraction (XRD), and Fourier Transformed Infrared Spectroscopy (FT-IR), Scanning electron microscopy (SEM-EDAX) were employed to assess the produced composites. The mechanical properties in terms of compressive strength and hardness test were also investigated. The in vitro study in simulated body fluid (SBF) was performed to assess the bioactivity of composites. The results proved that apatite resembling natural bone are formed faster and greater in the case the composite of HA containing 10% titania into chitosan-gelatin polymeric matrix when they are soaked in a simulated body fluid (SBF) than the composite containing 30% titania. The biocomposites containing HA with 10% titania are expected to be attractive for bioapplications as bone substitutes and scaffolds for tissue engineering in future.     

壳聚糖/明胶/苹果多酚复合膜的制备及性能研究

目的 以壳聚糖、明胶、苹果多酚为基材,制备一种具有优良性能的绿色环保复合材料。方法 用溶液共混法制备壳聚糖/明胶/苹果多酚共混膜,用土埋法测试其降解性,用红外光谱(FT–IR)、X射线衍射仪(XRD)、扫描电镜(SEM)等对其进行表征,并对其力学性能等进行测试。结果 壳聚糖/明胶/苹果多酚复合膜的机械强度随苹果多酚的添加量的增加先变大后减小,当苹果多酚添加量为1%时有较好的拉伸强度;壳聚糖、明胶、苹果多酚三者具有良好的相容性;复合膜生物降解性良好。结论 引入合适比例的苹果多酚可有效提升复合膜的力学性能,制得的可降解复合膜在绿色食品包装领域有广泛的应用前景。     

花青素-明胶/聚乙烯醇-淀粉复合膜制备与表征

目的 制备花青素明胶/聚乙烯醇淀粉双层复合膜,以期提高花青素单层膜的综合性能.方法 采用流延法分别制备紫薯、紫甘蓝、黑米、黑枸杞、玫瑰、玫瑰茄等6种花青素明胶/聚乙烯醇淀粉双层复合膜,并对比研究膜层的微观组织结构、含水率、力学性能及光学性能.结果 从红外光谱图中可以看出,双层复合膜分子结构没有出现新的特征峰,双层膜结合方式为物理结合,没有新的结构生成,且除紫甘蓝明胶/聚乙烯醇淀粉双层复合膜外,其余复合膜均存在明显的分层界线,2层结合处膜层结构均匀致密,结合良好.不同双层膜的含水率差异显著,而双层复合膜比花青素单层膜的含水率明显降低,不同双层膜的拉伸强度和断裂伸长率差异不显著,与单层花青素明胶复合膜相比,双层复合膜的拉伸强度和断裂伸长率大幅增加,其中紫薯双层膜的拉伸强度增加了75％,断裂伸长率增加了22.9％;所有双层复合膜的透光率相差不大,均在80％以上;与花青素明胶单层膜相比,双层膜的雾度增加了20％左右.结论 制备的双层膜改善了单层膜的力学性能,提高了花青素明胶单层膜的综合性能.     

纳米纤维素晶须/明胶复合膜的制备与结构及性能

明胶作为一种生物质材料,具有良好的成膜性能、阻氧性能。然而,明胶韧性差,遇水易溶胀等缺点在很大程度上限制其应用。文中以明胶为基体,纤维素晶须(CW)作为分散相,制备纳米纤维素/明胶生物基复合膜。采用透射电镜、扫描电镜、紫外分光光度计、溶胀及力学性能测试研究复合膜的结构与性能。结果表明,当晶须加入量为15%时,复合膜的溶胀度降低为纯明胶膜的1/4,表明纤维素晶须可改善明胶膜在水中的稳定性;当纤维素晶须含量为9%左右,不仅能改善明胶基体韧性,还提高了明胶基体的强度。     

成膜助剂对CCMC/PVA复合膜力学特性及生物降解特性的影响

采用流延成膜工艺制备了CCMC/PVA生物降解复合膜,研究了PVA、乙二醛以及PPE 3种成膜助剂对复合膜的力学性能和生物降解性能的影响。结果表明:添加一定量的成膜助剂,可以增强复合膜的机械性能、调控复合膜的生物降解性能;当PVA添加量为30%(质量分数)、乙二醛添加量为2%(质量分数)、PPE添加量为0.6%(质量分数)时,复合膜的拉伸强度可达22.5 MPa,断裂伸长率可达258%,固体琼脂平板培养50 d,微生物生长达到4级,土埋100 d,复合膜失重率达到92%。     

明胶/海藻酸钠(京尼平交联)互穿网络膜的制备与性能

为了提高海藻酸钠与明胶各自的性能,首先,以海藻酸钠和明胶为原料,以京尼平、CaCl2为交联剂,采用分步交联法制备了明胶/海藻酸钠互穿网络膜。然后,利用FTIR对明胶/海藻酸钠互穿网络结构进行了表征与分析,根据FTIR结果推测了互穿网络结构形成的机制。最后,探讨了京尼平的加入量和明胶与京尼平的质量比对互穿网络膜力学性能和交联度的影响,及海藻酸钠与明胶的质量比对互穿网络膜力学性能、断面形貌、热稳定性和吸水保水性能的影响。结果表明:当明胶与京尼平的质量比为200∶1、海藻酸钠与明胶的质量比为2∶1时,互穿网络膜具有最佳的力学性能、吸水保水性能和相容性;此外,互穿网络膜的力学性能也优于纯海藻酸钠膜与纯明胶膜的。明胶的加入提高了互穿网络膜在低温区的热稳定性,但降低了高温区的热稳定性。海藻酸钠与明胶之间可能以分子间作用力、氢键及离子键等相互作用,提高了二者各自的初始分解温度与最大热分解温度。研究解决了海藻酸钠与明胶力学性能差的问题,为拓展海藻酸钠在医用领域的应用提供参考。     

纤维素 / 聚碳酸亚丙酯多元醇共混膜的包装性能研究

用溶液铸膜工艺制备了纤维素 / 聚碳酸亚丙酯多元醇共混膜,以扫描电子显微镜、电子拉力机、差示量热扫描仪、透气透湿仪等试验仪器对共混膜进行了表征和性能测试。 研究表明:纤维素 / 聚碳酸亚丙酯多元醇共混膜的力学性能和透湿性能随聚碳酸亚丙酯多元醇含量的提高而提高,而透气性能则相反。 共混膜中聚碳酸亚丙酯多元醇含量为 30% 时共混膜的力学性能最好,共混膜中聚碳酸亚丙酯多元醇含量为 40% 时透湿性能最好,透气性能最差。