以低窄壳糖为载体的磁共振/荧光双功能成像分子探针的合成及性质研究  

Synthesis and Study on Properties of an Magnetic Resonance/Fluorescence Bifunctional Imaging Molecular Probe Using Low Degree of Polymerization and Narrow Molecular Weight Distribution Chitosan as Carrier

作　　者：刘春玲[1] 贾春满[1] 张岐[1] 钱亚骜 张德拉[1] 杨秋云[1] 杨仪宣 

机构地区：[1]海南大学海南省精细化工重点实验室热带多糖资源利用教育部工程研究中心,海南海口570228

出　　处：《精细化工》2016年第2期235-240,共6页Fine Chemicals

基　　金：国家自然科学基金(21261008;21471069;21562018);海南省国际科技合作专项(KJHZ2014-05)~~

摘　　要：通过微波辅助氧化法降解壳聚糖制得低聚窄分子量分布壳聚糖(低窄壳糖),LNCS6(聚合度为6,Mw/Mn=1.08),并以LNCS6为载体,键接7-羟基-8-醛基香豆素(CA)为荧光基团、二乙烯三胺五乙酸(DTPA)为络合基团,络合三价钆离子最终制得一种潜在的核磁共振(MR)/荧光双功能成像分子探针Gd[DTPA/CA-LNCS6]。研究了其磁共振成像效果以及荧光特性,并通过等温微量热滴定法(ITC)测定了产物与牛血清蛋白(BSA)之间的结合常数及热力学参数。结果表明,所得产物具有较高的体外磁共振成像效果〔r1=13.71 L/(mmol·s)〕,远高于目前临床使用的马根维显〔r1=3.63 L/(mmol·s)〕。同时,其具有显著的荧光特性(λmax=438 nm),与牛血清蛋白之间结合常数Ka>104,适用于血液输送,对这类探针精细化工中间体的合成具有较好的参考与借鉴作用。Low degree of polymerization（ DP） and narrow molecular weight distribution chitosan（ LNCS6）（ DP =6,Mw/ Mn= 1. 08） was prepared with the method of microwave-assisted oxidative degradation. It was used as a carrier molecular to link 7-hydroxyl-8-formylcoumarin（ CA） as the fluorescence emission group,diethylenetriaminepentaacetic acid（ DTPA） as complex of gadolinium ions to get the final product Gd[DTPA/CA-LNCS6] as an potential magnetic resonance（ MR） /fluorescence bifunctional imaging molecular probe. The magnetic resonance imaging（ MRI） efficiency and fluorescence properties were studied,and the binding constants and thermodynamic parameters between Gd[DTPA / CA-LNCS6] and bovine serum albumin（ BSA） were measured by isothermal titration calorimetry（ ITC）. The results showed that Gd[DTPA / CA-LNCS6]exhibited higher MRI relaxation〔r1= 13. 71 L /（ mmol·s） 〕,which was well above the clinically used magnevist 〔r1= 3. 63 L /（ mmol · s） 〕. Meanwhile,the product had significant fluorescence characteristics at 438 nm,and the binding constant between Gd[DTPA / CA-LNCS6]and BSA was over 104 which was suitable for blood transportation. This work has good reference for the synthesis of probes like such type of fine chemical intermediates.

关 键 词：低窄壳糖 磁共振成像 荧光特性 双功能成像分子探针 精细化工中间体 

分 类 号：O636.1[理学—高分子化学] R445[理学—化学]