检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
作 者:刘爱燕[1] 丁晨[1] 张小燕[1] 张岐[1,2] 龚玉珍[1] 黄燕[1]
机构地区:[1]江苏大学化学化工学院,江苏镇江212013 [2]海南大学海南省精细化工重点实验室,海南海口570228
出 处:《精细化工》2012年第5期429-433,467,共6页Fine Chemicals
基 金:国家自然科学基金(21166008);江苏省科技支撑计划(SBE201077304);江苏高校自然科学基金(10KJB430006);江苏大学高级人才引进基金(10JDG060);江苏大学学生科研立项(10A054)~~
摘 要:采用简单经济(与传统微乳法、热分解法等比较)的方法制备出一种磁性N-羧甲基壳聚糖造影剂。首先对壳聚糖的氨基进行羧甲基化制备N-羧甲基壳聚糖,然后在其链上采用原位生成Fe3O4纳米粒子的方法制备出磁性N-羧甲基壳聚糖,并对其进行了表征及性能的测试。热重分析结果表明,Fe3O4的生成量与N-羧甲基壳聚糖中羧甲基的含量有关,其生成量随着羧甲基含量的增加而增加,但当羧甲基的含量增加到一定程度时,Fe3O4的生成量达到某一峰值。透射电镜结果表明,生成的Fe3O4纳米粒子的粒径约为5~10 nm。磁共振成像结果显示,该磁性N-羧甲基壳聚糖的横向弛豫率为82.82 mmol/(L.s),高于超顺磁性氧化铁作为磁共振成像造影剂时R2需大于62 mmol/(L.s)的最低标准,可作为潜在的磁共振成像阴性造影剂。Magnetic N-carboxymethyl chitosan as a kind of potential magnetic resonance imaging contrast agent was synthesized through a simple and economic route(compared with such traditional methods as microemulsion and thermal decomposition).N-Carboxymethyl chitosan was first synthesized through the process of carboxymethylation of chitosan.Then,Fe3O4 nanoparticles were obtained by in situ reaction in the chains of N-carboxymethyl chitosan.The characterization and performance test of the magnetic N-carboxymethyl chitosan were carried out.The results of TGA show that the generation amount of Fe3O4 was related to the contents of carboxymethyl groups in N-carboxymethyl chitosan.It increased unceasingly along with the increase of the contents of carboxymethyl groups.But the generation amount of Fe3O4 reached a peak when the contents of catboxymethyl groups increased to a certain degree.The results of TEM indicated that the average grain size of the Fe3O4 nanoparticles was about 5~10 nm.The MRI depicted that the magnetic N-carboxymethyl chitosan provided a high transversal relaxation rate of 82.82 mmol/(L·s).It was higher than the minimum standard of R2,which was more than 62 mmol/(L·s),when superparamagnetic iron oxide was used as magnetic resonance imaging contrast agent.The magnetic N-carboxymethyl chitosan could be used as a kind of potential magnetic resonance imaging negative contrast agent.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:3.148.168.26