Amphiphilic hyperbranched fluoropolymers as nanoscopic 19F magnetic resonance imaging agent assemblies.
Amphiphilic hyperbranched fluoropolymers as nanoscopic 19F magnetic resonance imaging agent assemblies.
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DOI：
10.1021/bm800595b
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发表时间：
2008-10
影响因子：
6.2
通讯作者：
Wooley, Karen L.
中科院分区：
文献类型：
--
作者：
Du, Wenjun;Nystrom, Andreas M.;Zhang, Lei;Powell, Kenya T.;Li, Yali;Cheng, Chong;Wickline, Samuel A.;Wooley, Karen L.
合成了三种超支化含氟聚合物，并构建了它们的胶束作为潜在的~(19)F磁共振成像剂。以4-氯甲基苯乙烯(CMS)、丙烯酸月桂酯(LA)和1，1，1-tris(4′-(2″-bromoisobutyryloxy)phenyl)ethane为原料，首次合成了超支化星形核。聚合反应得到一个小核，其相对分子质量为5.5 kDa，PDI为1.6，可作为大分子引发剂。然后将甲基丙烯酸三氟乙酯(TFEMA)和丙烯酸叔丁酯(TBA)以不同的比例从芯层“接枝”，得到三种聚合物，其MN约为120 kDa，PDI值约为1.6-1.8。将叔丁酯基团酸解后，得到了两亲的超支化星形聚合物，其分子量约为100 kDa。这些结构在水溶液中形成胶束，得到了透射电子显微镜测得的直径为3-8 nm和DLS测得的流体力学直径为20-30 nm的胶束。通过~(19)F核磁共振波谱，这些胶束产生了窄的单次共振，半宽约为130赫兹。T1/t2参数分别约为500ms和50ms，且不受胶束组成和大小的显著影响。获得了这些含氟胶束的~(19)F磁共振体模图像，表明这些含氟胶束有可能作为一种新型的~(19)F磁共振试剂用于各种生物医学研究。
Three hyperbranched fluoropolymers were synthesized and their micelles were constructed as potential 19F MRI agents. A hyperbranched star-like core was first synthesized via ATR-SCVCP of 4-chloromethyl styrene (CMS), lauryl acrylate (LA) and 1,1,1-tris(4′-(2″-bromoisobutyryloxy)phenyl)ethane (TBBPE). The polymerization gave a small core with Mn of 5.5 kDa with PDI of 1.6, which served as a macroinitiator. Trifluoroethyl methacrylate (TFEMA) and tert-butyl acrylate (tBA) in different ratio were then “grafted” from the core to give three polymers with Mn of ca. 120 kDa and PDI values of ca. 1.6–1.8. After acidolysis of the tert-butyl ester groups, amphiphilic, hyperbranched star-like polymers with Mn of ca. 100 kDa were obtained. These structures were subjected to micelle formation in aqueous solution to give micelles having TEM-measured diameters ranging from 3–8 nm and DLS-measured hydrodynamic diameters from 20–30 nm. These micelles gave a narrow, single resonance by 19F NMR spectroscopy, with a half width of approximately 130 Hz. The T1/T2 parameters were ca. 500 ms and 50 ms, respectively, and were not significantly affected by the composition and sizes of the micelles. 19F MRI phantom images of these fluorinated micelles were acquired, which demonstrated that these fluorinated micelles maybe useful as novel 19F MRI agents for a variety of biomedical studies.
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影响因子：
56.9
作者：
FRECHET, JMJ;HENMI, M;GRUBBS, RB
通讯作者：
GRUBBS, RB
影响因子：
46.9
作者：
Ahrens, ET;Flores, R;Morel, PA
通讯作者：
Morel, PA
影响因子：
5.5
作者：
Cheng, Chong;Powell, Kenya T.;Wooley, Karen L.
通讯作者：
Wooley, Karen L.
影响因子：
5.5
作者：
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通讯作者：
Diamanti, S
影响因子：
15
作者：
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通讯作者：
Ahrens, Eric T.