改性壳聚糖硅杂化膜吸附铜离子性能研究

用氨丙基三乙氧基硅烷(KH550)分别与壳聚糖及羧甲基壳聚糖交联制备了纯壳聚糖硅杂化膜和羧甲基壳聚糖硅杂化膜.用红外光谱对2种杂化膜进行表征,并研究了2种杂化膜的溶胀性能及不同因素如铜离子浓度、膜质量、温度、pH和时间对杂化膜吸附重金属铜离子的影响.结果表明:2种杂化膜内皆有新键产生,引入了Si—C及Si—O—Si.与纯壳聚糖硅杂化膜相比,羧甲基壳聚糖硅杂化膜的溶胀性能降低.在室温下,溶液pH为6,Cu2+浓度为0.05 mol/L,分别吸附45 min和90 min,纯壳聚糖硅杂化膜和羧甲基壳聚糖硅杂化膜对铜离子都有较好的吸附.其中,羧甲基壳聚糖硅杂化膜上的铜离子吸附量要高于纯壳聚糖硅杂化膜.吸附动力学研究表明,2种杂化膜对Cu2+的吸附适合用二级动力学模型描述.     

聚乙二醇改性壳聚糖膜的制备与表征

研究利用聚乙二醇对壳聚糖进行改性,制备聚乙二醇改性壳聚糖膜,并对所得的膜进行表征。结果表明:采用0.25g聚乙二醇(PEG6000,98%)对壳聚糖(1.0g)进行改性,制备聚乙二醇改性壳聚糖膜,然后用BSA对改性后的壳聚糖进行吸附测试,测试数据显示5h吸附效果较理想。     

壳聚糖-Ca(Ⅱ)配位聚合物的合成及其性能表征

本文探讨了壳聚糖对Ca(Ⅱ）的吸附条件，并对其吸附行为进行了详细研究，发现Ca(Ⅱ)与壳聚糖在发生配位反应形成壳聚糖－钙（Ⅱ）配位聚合物的同时，也产生了吸附作用。动用元素分析法，红外光谱法和此外吸收法对原料及配合物的结构及光学性能进行了表征。     

离子交换树脂吸附酒精中杂醇油的醛的机理研究

本文系统地研究了离子交换树脂吸附酒精中杂醇油和醛的机理。离子交换树脂吸附酒精中杂醇油和等温线可用兰格缪尔等温方程来描述，但吸附醛的等温线则可用弗罗因德利奇等温方程来描述。在杂醇油－醛－水－乙醇体系中，离子交换树脂优先吸附醛。处理液的酒精度和ＰＨ值对离子交换树脂吸附杂醇油和醛的影响不大。     

壳聚糖膜的制备及对植物色素富集作用的研究

本文对甲壳素、壳聚糖膜的制备及性能进行了研究，探讨了壳聚糖膜对植物色素的富集作用。实验证明：2％壳聚糖膜对萝卜红色素有较好的富集作用，富集率达84％。为天然色素的提取提供了一条新的途径。     

阳离子交换膜对阳离子艳红X-5GN的吸解性能

研究了阳离子交换膜对阳离子艳红X-5GN的吸附和解吸性能。结果表明,吸附过程主要发生在前30min,吸附符合伪二级动力学模型;Langmuir吸附模型能更好的描述吸附过程。染料水溶液中加入不同浓度无机缓染剂Na2SO4对吸附有一定影响;用乙醇、氯化钠,乙醇和氯化钾溶液的混合液来解吸,解吸率可达98%以上,且该阳离子交换膜的重复利用性很好。     

互穿网络膜交联棉织物对活性染料的吸附研究

文中制备了一种壳聚糖与明胶互穿网络膜交联棉织物吸附材料,以活性红K-2BP染液作为吸附对象,探讨了p H值、时间、温度、染液浓度、染液体积等因素在壳聚糖与明胶互穿网络膜交联棉织物对活性红K-2BP染液吸附过程中,对其吸附性能的影响。并与未经整理的棉织物的吸附性能进行了对比,同时对吸附材料的重复使用性能进行了测试。结果表明:活性红K-2BP染液p H值为3时吸附效率较高,随着温度的升高、时间的延长吸附容量逐渐增大,适当降低染液浓度或染液体积会提高吸附率;与未经整理棉织物相比,整理后棉织物的吸附性能明显提高,且脱附效果良好,可重复使用。     

磁性Fe_3O_4/壳聚糖复合微球的制备及其对苹果汁有机酸的吸附

为分离苹果汁中的有机酸,采用反相悬浮交联法制备磁性Fe_3O_4/壳聚糖复合微球。利用扫描电子显微镜、激光粒度仪、X射线衍射仪、超导量子干涉磁测量系统等对复合微球进行表征。同时测定了特定磁场条件下复合微球在不同时间、不同pH值下的回收率以及对苹果汁中有机酸的重复吸附性能。结果表明:制备的微球呈规则球形,分散性良好,粒径范围22～158μm;Fe_3O_4纳米颗粒约占复合微球总质量的38.66%,壳聚糖包埋过程并没有改变Fe_3O_4的尖晶石结构;复合微球饱和磁化强度35.98 emu/g,磁场作用下2 min回收率可达99.99%以上;连续3次吸附苹果汁中有机酸,平衡吸附量仍可达到109.92 mg/g,有机酸回收率86.86%。综上,壳聚糖与Fe_3O_4纳米颗粒相结合制备的磁性Fe_3O_4/壳聚糖复合微球磁响应强、回收率高,对苹果汁中有机酸具有良好的吸附性能,环保高效,可反复使用。     

离子交换树脂吸附酒精中杂醇油和醛的机理研究

本文系统地研究了离子交换树脂吸附酒精中杂醇油和醛的机理。离子交换树脂吸附酒精中杂醇油的等温线可用兰格缪尔（Ｌａｎｇｍｕｉｒ）等温方程来描述，但吸附醛的等温线则可用弗罗因德利奇（Ｆｒｅｕｎｄｉｉｃｈ）等温方程来描述。在杂醇油－醛－水－乙醇体系中，离子交换树脂优先吸附醛。处理液的酒精度和ｐＨ值对离子交换树脂吸附杂醇油和醛的影响不大。     

茧纸的制备及其性能测试

探讨了制备茧纸的适宜条件。并对茧纸的性能、脱胶方法以及对壳聚糖的吸附效果进行了研究。结果表明，在适当的营茧条件下，可制得具有良好机械强度和透气性的茧纸：为保持茧纸形状，应采用高温高压水脱胶：经壳聚糖吸附后，茧纸的机械性能得以进一步加强。     

壳聚糖改性蒙脱石对蔗糖溶液中酚酸的吸附性能研究

通过共沉淀法制备壳聚糖改性蒙脱石并用于蔗糖溶液中酚酸的吸附。通过SEM、FT-IR、XPS和BET对其进行表征,由表征结果可知:改性过程成功地将壳聚糖负载到蒙脱石表面,制备出壳聚糖改性蒙脱石;改性蒙脱石等电点为7.84,主要通过静电力和胺基吸附蔗糖溶液中的没食子酸。吸附试验结果表明改性后的蒙脱石对没食子酸吸附性能提高,壳聚糖改性蒙脱石对蔗糖溶液中没食子酸吸附的最佳pH为7.0,平衡时间为600 min。壳聚糖改性蒙脱石对没食子酸的吸附过程更加符合Freundlich模型和准二级吸附动力学方程,吸附过程主要为多分子层吸附和化学吸附,饱和吸附量达到58.82 mg/g。壳聚糖改性蒙脱石具有良好的再生性能,且对蔗糖溶液中酚酸吸附效果良好,是一种有前景的糖用澄清剂。     

Effect of polymer surface modification on polymer-protein interaction via hydrophilic polymer grafting

ABSTRACT:  Surface modification of flat sheet ultrafiltration membranes, polyethersulfone (PES), was investigated to improve the hydrophilicity of the membrane surface thereby reducing adsorption of the proteins onto the membrane. Grafting of hydrophilic polymers onto UV/ozone-treated PES was used to improve the hydrophilicity of the commercial PES membranes. Hydrophilic polymers, that is, poly(vinyl alcohol) (PVA), polyethylene glycol (PEG), and chitosan, were employed to graft onto PES membrane surfaces because of their excellent hydrophilic property. The surfaces of modified PES membranes were characterized by contact angle measurement, FTIR, and AFM. The FTIR spectra indicated that PES membranes were successfully modified by grafting of the hydrophilic polymers. The modified PES membranes showed 20% to 50% reduction in contact angle measurements in comparison with those of the virgin PES membrane. The tapping mode AFM technique was employed to investigate the changes of surface topography, cross-section, and root mean square roughness of the modified PES membrane surfaces. The modified PES membranes showed elevated roughness (ranging from 7.0 to 25.7 nm) compared with that of the virgin PES membrane (2.1 nm). It is concluded that grafting of PVA, PEG, or chitosan onto UV/ozone-treated PES membranes increases hydrophilicity and lowers protein adsorption by 20% to 60% compared to the virgin PES membrane. Among the 3 hydrophilic polymers studied, PEG showed the most favorable result in terms of contact angle and protein adsorption.     

Antibacterial effects of chitosan solution against Legionella pneumophila, Escherichia coli, and Staphylococcus aureus

Chitosan has been shown to have antibacterial activities on the growth of a wide variety of bacteria. Chitosan solution has been sold commercially for use as an antibacterial agent. Chitosan solution contains not only chitosan but also organic acids as solvents and desalted Japan Sea Proper Water (dJSPW). We aimed to clarify whether chitosan solution has antibacterial activity against bacteria invading bath water, and then to explore the causative factor among these ingredients. The antibacterial activity of full-strength chitosan solution and of 10(2)- and 10(4)-fold chitosan solution diluted with purified water was studied against Legionella pneumophila serogroups 1 (L. pneumophila SG1) and 6 (L. pneumophila SG6), Escherichia coli (E. coli), and Staphylococcus aureus (S. aureus) for 7 days at 37 degrees C. To clarify the causative factor in the antibacterial activity against E. coli, the antibacterial activities of the full-strength and diluted chitosan solutions for 24 h were examined. L. pneumophila SG1 and SG6, and E. coli could not survive in the chitosan solution or in the 10(2)-fold dilute solution for over a day at 37 degrees C. The cells of S. aureus were found to have decreased more than 2.46 log cfu/ml after 1 day of incubation, not only in the chitosan solutions, but also in phosphate buffer solution as a control. No inhibitory effect of dJSPW on the growth of the bacteria was observed. The antibacterial activity of the chitosan solution was lower compared with those of the organic acids solutions, and it increased with decreasing pH value. We observed the antibacterial activity of chitosan solution against L. pneumophila SG1 and SG6, and E. coli, suggesting it may be due to the decreased pH value derived from organic acids rather than from chitosan itself or dJSPW.     

非生物性因素对壳聚糖抗菌活性的影响

以具有代表性的两类病原菌:金黄色葡萄球菌和大肠杆菌为实验菌种,研究了不同的酸溶液、金属离子、离子强度和pH等非生物性因素对壳聚糖抗菌活性的影响。结果表明:在壳聚糖的酸溶液中,低碳数的有机酸比高碳数的有机酸和常见的无机酸更有利于壳聚糖抗菌活性的发挥;在pH6.0的环境中,壳聚糖的抗菌活性最强;由于与壳聚糖的螯合作用,Zn2+的加入对于壳聚糖的抗菌效率影响最大,Mg2+的影响相对最小;离子强度的增大可以更好地提高壳聚糖的抗菌活性。     

磁性壳聚糖改性对高岭土吸附蔗糖溶液中咖啡酸性能的影响

目的:研究磁性壳聚糖改性高岭土对模拟蔗汁中咖啡酸的吸附特性。方法:通过共沉淀法将壳聚糖、纳米四氧化三铁与高岭土结合制备成磁性壳聚糖改性高岭土,通过FT-IR、VSM和SEM表征高岭土改性前后表面结构和基团变化,采用吸附试验研究磁性壳聚糖改性高岭土对咖啡酸的吸附特性。结果:改性后壳聚糖和纳米Fe₃O₄成功地负载到了高岭土上并提升了其对咖啡酸的吸附性能,磁性壳聚糖改性高岭土的等电点为4.54,酸性条件有利于咖啡酸的去除,并在240 min时达到吸附平衡。磁性壳聚糖改性高岭土对咖啡酸的吸附过程更符合准二级动力学和Langmuir等温线吸附模型,其吸附过程主要为化学吸附和单分子层吸附,热力学研究表明吸附过程为自发吸热过程。结论:磁性壳聚糖改性高岭土对蔗汁中咖啡酸具有较强吸附性能,可作为糖用澄清剂用于蔗汁中咖啡酸的吸附处理。     

羧甲基壳聚糖对啤酒酵母脱苦的特性研究

为了脱除啤酒酵母泥中主要的苦味,利用羧甲基壳聚糖(CMCS)吸附啤酒酵母泥中的苦味物质,研究表明在35 min内,羧甲基壳聚糖对破壁的酵母泥脱苦速率大于未破壁酵母泥的脱苦速率。通过傅里叶变换红外(FT-IR)光谱仪对吸附前后羧甲基壳聚糖的表征以及对羧甲基壳聚糖吸附啤酒酵母中苦味物质过程中的吸附热力学特性、吸附动力学的分析,研究了羧甲基壳聚糖对啤酒酵母脱苦特性。结果表明:羧甲基壳聚糖脱苦未破壁和破壁酵母泥的化学基团可能相同,羧甲基壳聚糖对啤酒酵母泥脱苦过程中参加反应的主要基团是-COOH,-OH也参与了反应。羧甲基壳聚糖对未破壁和破壁的啤酒酵母泥的吸附热力学特性符合Langmuir等温线性模型,吸附动力学过程遵循拟二级动力学模型,吸附过程以单层化学吸附为主。     

改性磁性壳聚糖对胭脂红的吸附性能评价

以纳米Fe₃O₄、壳聚糖为材料,采用反相悬浮交联法,用三乙胺做改性剂制备改性磁性壳聚糖,研究其对胭脂红色素的吸附性能影响,考察时间、pH、温度及胭脂红的初始浓度等四个因素对改性磁性壳聚糖吸附胭脂红溶液吸附效果的影响,并对吸附动力学模型、吸附等温模型、吸附热力学和吸附再生性能进行初步探讨。结果表明,当pH=3,吸附时间为270 min,温度为50℃,初始浓度为100 mg/L时,改性磁性壳聚糖对胭脂红溶液的吸附率达到最高,为96.72%。改性磁性壳聚糖对胭脂红溶液的吸附动力学数据符合准二级动力学模型,吸附等温线数据符合Langmuir模型,热力学数据拟合得出ΔH>0,ΔS>0,ΔG<0,得出此反应是吸热反应。经过三次吸附-解析实验,吸附率和解析率仍在40%以上。     

Removal of salt and organic acids from solution used to season salted Japanese apricots (ume) by electrodialysis, precipitation and adsorption

With the aim of repeatedly reusing the solution used to season salted ume (Japanese apricot), we investigated its desalting and deacidification by electrodialysis, precipitation, and adsorption. Although NaCl and acids could be easily removed from used seasoning solution by electrodialysis, useful substances such as amino acids were removed at the same time. Precipitation using Ca(OH)2 could remove only organic acids, but the treated solution became bitter. Two weakly basic commercial resins, DIAION WA30 and Chitopearl CCS, adsorbed organic acids selectively. Chitopearl CCS in particular selectively adsorbed citric acid in the used seasoning solution without also adsorbing useful substances. The equilibrium data of a citric acid, which was a main organic acid, were correlated by the Langmuir equation. The saturation capacity decreased with increasing concentrations of NaCl in the solution but the equilibrium constant did not change. By combining electrodialysis and adsorption, NaCl and organic acids could be removed while amino acids largely remained. The resultant solution was considered to be suitable for repeated reuse.     

载银甲壳素纤维的制备与抗菌性能研究

将羟基功能化纳米银应用于载银甲壳素纤维的制备,利用分光光度法研究了甲壳素纤维对羟基功能化纳米银的吸附性能和吸附机理;测试了不同银含量载银甲壳素纤维的抗菌性能;采用扫描电镜(SEM)和光电子能谱(XPS)对载银甲壳素纤维的微观形貌和元素成分进行了分析。研究结果表明,甲壳素纤维对羟基功能化纳米银具有较高的吸附能力,最高吸附量可达3 390 mg/kg;纳米银颗粒在甲壳素纤维表面分布均匀,且未被氧化;另外,抗菌测试结果表明载银甲壳素纤维具有优异的抗菌性能,当银含量达到1 000 mg/kg时,其对E.coli和S.aureus的抑菌率均可达99%以上。     

Separation and purification of lysozyme by Reactive Green 19 immobilised membrane affinity chromatography

A poly(hydroxyethylmethacrylate)/chitosan (pHEMA-chitosan) composite membrane was prepared by UV-initiated photo-polymerisation. A dye ligand (i.e. Reactive Green 19; RG 19) was immobilised onto the membrane. The water content of the dye ligand-immobilised membrane was 50 ± 2% and the amount of immobilised Reactive Green 19 on the membrane was 0.865 μmol/ml. The rates of adsorption of lysozyme on plain composite and dye ligand-immobilised composite membranes were measured in a stirred cell. The adsorption capacity of the composite membrane was determined by changing pH and the concentration of lysozyme in the adsorption medium. Separation and purification of lysozyme from aqueous solution and egg white were investigated, respectively. The lysozyme adsorption capacity of the RG 19 immobilised membrane was 60.8 mg/ml. The adsorption capacity of the plain composite membrane was 7.2 mg/ml. Separation and purification were monitored by determining the lysozyme activity using Micrococcus lysodeikticus as substrate. The lysozyme was purified 25.4-fold in a single step with a recovery 82%, as determined by HPLC. The membranes were stable when subjected to sanitization with sodium hydroxide after repeated adsorption-elution cycles.