乙二胺丙酰化交联壳聚糖微球对甲基橙的吸附性能

通过丙烯酰化交联壳聚糖微球(AGCS)上的丙烯酰基团与乙二胺的Michael加成反应,制备乙二胺丙酰化交联壳聚糖微球(EAGCS)。分别采用傅里叶变换红外光谱(FT-IR)、X射线光电子能谱(XPS)和X射线衍射(XRD)表征了EAGCS的结构,利用激光粒度分析仪进行了粒径分布分析,考察了甲基橙(MO)溶液pH、温度、浓度和EAGCS用量对EAGCS吸附性能的影响。结果表明:EAGCS为球形,微球的体积平均粒径为57.4μm,粒径分布系数1.53;在最佳条件下,EAGCS的吸附去除率为99.6%,吸附容量可达545.40 mg·g~(-1),吸附过程属于自发放热过程,吸附动力学符合二级动力学,吸附过程可采用Langmuir和Freundlich等温吸附模型来描述。     

交联壳聚糖微球的制备及其对不同pH有机染料的吸附性能

本文以壳聚糖为原料,戊二醛为交联剂,采用乳化交联法制备了交联壳聚糖微球。并通过红外光谱仪(FT-IR)、X射线衍射仪(XRD)、扫描电镜(SEM)对壳聚糖和交联壳聚糖微球的结构与形貌进行表征,使用紫外/可见分光光度计测试了甲基橙溶液的吸收波长及吸光度。主要研究了不同p H条件下交联壳聚糖微球对甲基橙溶液的吸附脱色效果。结果表明:交联壳聚糖微球形状规则、表面光滑,其粒径为100μm左右;当甲基橙溶液p H值为3时,吸附速率最快;动力学研究结果表明该吸附过程符合准二级吸附动力学方程模型。     

丙烯酰化壳聚糖的制备

设计了一种壳聚糖的改性方法。以壳聚糖(CS)和丙烯酸(AA)为原料,1-乙基-3-(3-二甲氨基丙基)碳二亚胺盐酸盐(EDC)为交联结合剂,用丙烯酰化的方式改性壳聚糖,幵成功地通过红外光谱法和核磁共振氢谱法测定粒子微观组成,验证了丙烯酰化壳聚糖的合成。得到带有碳碳双键的丙烯酰化交联壳聚糖,可以用于迚一步制成微凝胶,微球可以同药物一起被加工成丸剂、乳剂、微球、微囊、薄膜等制成控制释放体系,达到控制药物释放、延长药物疗效的作用。     

交联壳聚糖多孔微球吸附亮绿的研究

利用液体石蜡作有机分散介质,戊二醛作交联剂,制备了交联壳聚糖多孔微球,采用SEM对壳聚糖微球的形貌、大小进行了表征,研究交联壳聚糖微球对亮绿的吸附性能,探讨交联壳聚糖多孔微球用量、亮绿初始浓度、pH值、吸附时间、吸附温度的影响.结果表明,室温下,交联壳聚糖微球粒径为0.5～1.0 mm,亮绿初始浓度10 mg·L-1,pH=6,振摇30 min时,吸附量达1.22 mg·g-1;CODCr去除率达73%.亮绿初始浓度越大,吸附量越大,吸附速率越大;吸附剂用量越大,平衡吸附量越小,吸附速率越大.交联壳聚糖微球对亮绿具有很高的吸附容量和较快的吸附速率,再生重复使用,其脱色率仍达90%以上.等温吸附较好符合Freundlich方程.     

交联壳聚糖微球树脂对Cu(Ⅱ)吸附性能研究

采用反相悬浮法,以戊二醛为交联剂,以环己烷为致孔剂制备交联壳聚糖微球树脂(CCMR);通过静态吸附试验研究树脂对Cu(Ⅱ)的吸附行为。利用金相显微镜和比表面积仪对交联壳聚糖微球树脂(CCMR)的表观形貌和比表面积进行表征;通过紫外可见光谱考察了Cu(Ⅱ)初始浓度对吸附性能影响,研究其吸附动力学。结果表明,随着致孔剂用量的增加,交联壳聚糖微球树脂比表面积增大,吸附性能增强,其中添加环己烷100 m L,乙酸乙酯5 m L制备交联壳聚糖微球树脂对浓度为8 mg/m L的Cu(Ⅱ)溶液的平衡吸附容量可达190 mg/g,吸附性能较好,吸附过程符合准二级吸附动力学模型。     

交联壳聚糖微球对喹乙醇吸附性能的研究

以壳聚糖为原料,乙酸乙酯为致孔剂,环氧氯丙烷为交联剂,通过交联法制备出改性壳聚糖,考察了交联壳聚糖微球对喹乙醇吸附的影响。结果表明,V(壳聚糖)∶V(乙酸乙酯)∶V(环氧氯丙烷)=30∶1∶1时,制备的交联壳聚糖微球对喹乙醇吸附性能较好;红外光谱表明,环氧氯丙烷与壳聚糖发生反应;扫描电镜分析验证环氧氯丙烷用量对交联壳聚糖微球吸附性能有一定影响;吸附动力学曲线得知交联壳聚糖微球在3 h对喹乙醇吸附达到平衡,有较好的吸附速度;与类似物(喹烯酮和乙酰甲喹)吸附特性比较得知,交联壳聚糖微球对喹乙醇有较好的选择吸附性。     

磁性交联壳聚糖对水溶液中铀(Ⅵ)离子的吸附行为

采用纳米Fe₃O₄作为磁流体包埋、戊二醛和硫脲进行交联壳聚糖,制备磁性交联壳聚糖（TTG-MCTS）。红外光谱（FTIR）和X射线能谱（EDS）分析结果表明,壳聚糖改性后,吸附能力得到提高,铀(Ⅵ)成功地被吸附在TTG-MCTS上。系统研究了溶液pH值、铀(Ⅵ)初始浓度及振荡时间对吸附容量的影响,继而得到最佳工艺条件。吸附过程用Langmuir等温式拟合优于用Freundlich等温式,最大吸附容量为161.3 mg·g^-1。较之拟一级动力学模型,拟二级动力学模型能更好地拟合实验数据。     

磁性壳聚糖交联环糊精复合微球制备及吸附性能的研究

以反相悬浮交联法制备磁性壳聚糖交联β-环糊精复合微球。采用光学显微镜、红外光谱（IR）、振动样品磁强计（VSM）对微球进行表征,并研究其对模型蛋白（木瓜蛋白酶）的吸附行为。结果表明,微球为完整的球形,具有良好的磁响应性。模型蛋白在微球上的吸附关系既可用Langmuir方程描述,又可用计量置换吸附Freundlich方程描述,且更符合Freundlich方程描述;聚丙烯酰胺凝胶电泳(SDS—PAGE)结果表明吸附的模型蛋白能从磁性粒子表面完整的脱附下来。     

交联壳聚糖复合微球对F-的吸附性能研究

以壳聚糖(CTS)包合氧化铝经戊二醛交联反应制备了复合微球作为氟离子吸附剂。主要研究了复合微球对F-的吸附模型和吸附动力学,并考察了再生次数对吸附容量的影响。结果表明复合微球对F-有很强的吸附作用和较快的吸附速率;吸附行为符合Freundlich模型,为吸热过程,吸附表观活化能△E=53.71kJ/mol;复合微球经碱液洗脱再生后能够多次使用。     

季铵盐改性壳聚糖微球对含铬废水的吸附性能

用2,3-环氧丙基三甲基氯化铵对壳聚糖进行改性得到壳聚糖季铵盐,进一步通过乳化交联法合成壳聚糖季铵盐微球,采用傅里叶变换红外光谱（FT-IR）、差热热重分析（TG-DTG）、X-衍射衍射（XRD）和扫描电镜（SEM）对其进行表征分析。此外,研究了壳聚糖季铵盐的浓度、油水比、交联剂用量对合成的壳聚糖季铵盐微球吸附Cr(Ⅵ)性能的影响,并考察了重铬酸钾初始浓度、pH值、壳聚糖季铵盐微球添加量对Cr(Ⅵ)吸附效果的影响。结果表明：HACC浓度为0.8%(w/V)、油水比为8∶1、壳聚糖季铵盐与交联剂质量比为1.64的条件下,可以制备出球型圆整、分散性好的壳聚糖季铵盐微球。在酸性条件和较低浓度的重铬酸钾均有利于壳聚糖季铵盐微球对Cr(Ⅵ)的吸附。     

Human serum albumin (HSA) adsorption with chitosan microspheres

In this study, chitosan microspheres were prepared and characterized for adsorption of human serum albumin (HSA) as affinity sorbent. The chitosan microspheres were obtained with a “suspension crosslinking technique” in the size range of 30–700 μm by using a crosslinker, i.e., glutaraldehyde. The chitosan microspheres used in HSA adsorption studies were having the average size of 170 ± 81 μm. Adsorption medium pH and the initial HSA concentration in the adsorption medium were changed as 4.0–7.0 and 0.5–2.0 mg HSA/mL, respectively, to investigate the HSA adsorption capacity of chitosan microspheres. Maximum HSA adsorption (i.e., 11.35 mg HSA/g chitosan microspheres) was obtained at pH 5.0 and 1.5 mg HSA/mL of the initial HSA concentration in the adsorption medium was obtained as the saturation value for HSA adsorption. A very common dye ligand, i.e., Cibacron Blue F3GA was attached to the chitosan microspheres to increase the HSA adsorption capacity. Actually, the HSA adsorption capacity was increased up to 15.35 mg HSA/g chitosan microspheres in the case of Cibacron Blue F3GA attached to chitosan microspheres used. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 86: 3035–3039, 2002     

Preparation,characterization, and adsorption properties of chitosan microspheres crosslinked by formaldehyde for copper (II) from aqueous solution

The chitosan microspheres crosslinked by formaldehyde were prepared by spray drying method and used as an adsorbent for copper (II) from aqueous solution. A batch adsorption system was applied to study the adsorption of copper (II) from aqueous solution by chitosan microspheres. The maximum adsorption capacity of the chitosan microspheres for copper (II) was 144.928 mg/g at pH 6.0. Langmuir adsorption model was found to be applicable in interpreting the adsorption process. To elucidate the adsorption mechanism, the chitosan microspheres before and after copper (II) adsorption were further characterized by Fourier transform infrared spectra, zeta potential analysis, and scanning electron microscope. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Spray-Dried Chitosan Microspheres as a pDNA Carrier

Spray-dried chitosan microparticles with controlled size were prepared and crosslinked with the biocompatible reactant d,l-glyceraldehyde. Glutaraldehyde, the conventional cross-linking agent for proteins, was used as a control. The crosslinking degree was characterized through thermal analysis, X-ray diffraction, and infrared spectroscopy. In addition, the crosslinking effects were analyzed in terms of particle size, swelling capability, and surface charge. By properly choosing d,l-glyceraldehyde concentration and crosslink time, a high degree of control was achieved over the physical properties of particles. Yields around 78% as well as images obtained through fluorescence microscopy demonstrated the capability of the crosslinked chitosan microspheres to pDNA complexation.     

表面修饰聚乙烯亚胺的壳聚糖微球对十二烷基苯磺酸钠的吸附特性

采用乳化交联法制备交联壳聚糖微球(CCS),在其表面接枝聚乙烯亚胺(PEI),得到系列具有不同离子交换容量(IEC)的PEI修饰交联壳聚糖微球(PEI-CCS),对其进行表征,考察了其对十二烷基苯磺酸钠(SDBS)的静态吸附特性. 结果表明,PEI-CCS平均粒径为85 mm,IEC最高达1275 mmol/g,远高于CCS的418 mmol/g. 酸性条件下,PEI-CCS的胺基质子化,带正电荷,能与溶液中的阴离子吸附结合,对SDBS有良好的吸附能力. 吸附过程自发放热,可用准二级动力学模型和Langmuir吸附等温模型描述. PEI-CCS对SDBS的最大吸附量随IEC增加而增大,IEC=1275 mmol/g的PEI-CCS的最大吸附量为1487.61 mg/g,是CCS最大吸附量(510.20 mg/g)的2.92倍,吸附-脱附7次循环后,吸附量下降17.8%. PEI-CCS具有良好的重复使用性.     

Synthesis and characterization of modified chitosan microspheres: Effect of the grafting ratio on the controlled release of nifedipine through microspheres

The grafting of acrylamide onto a chitosan backbone was carried out at three acrylamide concentrations (polymer/monomer ratio = 1:1, 1:2, and 1:3). The synthesis of the grafted polymer was achieved by K₂S₂O₈‐induced free‐radical polymerization. Microspheres of polyacrylamide‐g‐chitosan crosslinked with glutaraldehyde were prepared to encapsulate nifedipine (NFD), a calcium channel blocker and an antihypertensive drug. The microspheres of polyacrylamide‐g‐chitosan were produced by a water‐in‐oil emulsion technique with three different concentrations of glutaraldehyde as the crosslinking agent. Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC) were used to characterize the grafted copolymers, and the microspheres were prepared from them. FTIR and DSC were also used to analyze the extent of crosslinking. The microspheres were characterized by the particle size; the water transport into these microspheres, as well as the equilibrium water uptake, were studied. Scanning electron microscopy confirmed the spherical nature of the particles, which had a mean particle size of 450 μm. Individual particle dynamic swelling experiments suggested that with an increase in crosslinking, the transport became case II. The release of NFD depended on the crosslinking of the network and on the amount of drug loading. Calculating the drug diffusion coefficients with the initial time and later time approximation method further supported this. The drug release in all 27 formulations followed case II transport, and this suggested that the time dependence of the NFD release followed zero‐order kinetics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 2940–2949, 2003     

氯化体系中环硫氯丙烷交联壳聚糖树脂对Au（Ⅲ）的吸附特性

以环硫氯丙烷为交联剂，合成了环硫氯丙烷交联壳聚糖（CCCS）树脂，并对其进行了SEM和FTIR表征，研究了该树脂对Au（Ⅲ）的吸附动力学、吸附平衡等吸附特性。结果表明，环硫氯丙烷在交联过程中发生开环反应，产生了巯基—HS，在吸附过程中CCCS树脂中的—NH2和—HS参加了与Au（Ⅲ）的配位;吸附反应速率遵循Lagergren二级速率方程所描述的规律，表观活化能为16.039 kJ·mol-1;其等温吸附符合Langmuir方程和Freundlich方程，吸附过程为物理吸附的放热吸附。     

壳聚糖/纤维素复合微球对Cu2+的吸附

制备壳聚糖/纤维素(CS/CE)和交联壳聚糖/纤维素(ECS/CE)复合微球,用于吸附重金属离子,考察了微球对Cu2+的吸附性能。溶解性测试表明交联反应可提高微球在酸性介质中的化学稳定性。静态吸附表明,CS/CE和ECS/CE均能有效吸附Cu2+,pH 6附近吸附容量最大。吸附等温线与Langmuir和Freundlich模型均吻合,由Lang-muir模型得到的Cu2+饱和吸附容量分别为38.76 mg/g(CS/CE)和34.13 mg/g(ECS/CE)。CS/CE和ECS/CE对Cu2+的吸附初期为内扩散控制,但后期为配合反应控制。FTIR和X-射线光电子能谱(XPS)分析表明,壳聚糖中的N为Cu2+的主要吸附位,发生表面配合吸附。     

硅胶负载交联壳聚糖树脂的制备及吸附性能

以壳聚糖、硅胶为主要原料制备了一种硅胶负载交联壳聚糖树脂,采用红外光谱(IR)、X-衍射(XRD)和扫描电镜(SEM)对其进行结构性能表征,并研究了树脂对金、银离子的吸附行为。重点考察了交联剂用量、介质pH值和初始离子浓度等因素对树脂材料吸附率的影响,试验结果表明,该树脂对金银离子的吸附率均大于90%。对于金离子的吸附而言,控制pH值在4,吸附时间90 min时吸附率最高;对于银离子的吸附而言,控制pH值在4~6,吸附时间100 min时吸附率最高。离子初始质量浓度对树脂材料的吸附率影响不大。     

交联氧化铝-壳聚糖新杂化吸附剂的制备及去除废水中Cu(Ⅱ)(英文)

A novel biosorbent was developed by coating chitosan,a naturally and abundantly available biopolymer,on to activated alumina based on oil shale ash via crosslinking.The adsorbent was characterized by various techniques,such as Fourier transform infrared spectroscopy,scanning electron microscopy,thermogravimetric-differential thermal analysis,and X-ray photoelectron spectroscope.Batch isothermal equilibrium adsorption experiments were condcted to evaluate the adsorbent for the removal of Cu(Ⅱ) from wastewater.The effect of pH and agitation time on the adsorption capacity was also investigated,indicating that the optimum pH was 6.0.The equilibrium adsorp-tion data were correlated with Langmuir and Freundlich models.The maximum monolayer adsorption capacity of chitosan coated alumina sorbent as obtained from Langmuir adsorption isotherm was found to be 315.46 mg·g-1 for Cu(Ⅱ).The adsorbent loaded with Cu(Ⅱ) was readily regenerated using 0.1 mol?L?1 sodium hydroxide solution.All these indicated that chitosan coated alumina adsorbent not only have high adsorption activity,but also had good stability in the wastewater treatment process.