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41.
Comparative Assessment of Complex Stabilities of Radiocopper Chelating Agents by a Combination of Complex Challenge and in vivo Experiments 下载免费PDF全文
Shanna Litau Dr. Uwe Seibold Alicia Vall‐Sagarra Prof. Dr. Gert Fricker Prof. Dr. Björn Wängler Priv.‐Doz. Dr. Carmen Wängler 《ChemMedChem》2015,10(7):1200-1208
For 64Cu radiolabeling of biomolecules to be used as in vivo positron emission tomography (PET) imaging agents, various chelators are commonly applied. It has not yet been determined which of the most potent chelators—NODA‐GA ((1,4,7‐triazacyclononane‐4,7‐diyl)diacetic acid‐1‐glutaric acid), CB‐TE2A (2,2′‐(1,4,8,11‐tetraazabicyclo[6.6.2]hexadecane‐4,11‐diyl)diacetic acid), or CB‐TE1A‐GA (1,4,8,11‐tetraazabicyclo[6.6.2]hexadecane‐4,11‐diyl‐8‐acetic acid‐1‐glutaric acid)—forms the most stable complexes resulting in PET images of highest quality. We determined the 64Cu complex stabilities for these three chelators by a combination of complex challenge and an in vivo approach. For this purpose, bioconjugates of the chelating agents with the gastrin‐releasing peptide receptor (GRPR)‐affine peptide PESIN and an integrin αvβ3‐affine c(RGDfC) tetramer were synthesized and radiolabeled with 64Cu in excellent yields and specific activities. The 64Cu‐labeled biomolecules were evaluated for their complex stabilities in vitro by conducting a challenge experiment with the respective other chelators as challengers. The in vivo stabilities of the complexes were also determined, showing the highest stability for the 64Cu–CB‐TE1A‐GA complex in both experimental setups. Therefore, CB‐TE1A‐GA is the most appropriate chelating agent for *Cu‐labeled radiotracers and in vivo imaging applications. 相似文献
42.
A linear polyether, 1, 13-bis[8-qulnoly]-l,4,7,10,13-pentaoxa-trldecane (K-5) and an aza-crown ether, 4,13-didodecyl-1,7,10,16-tetraoxadiazacyclooctadecane (K22DD) when combined with thenoyltrlfluoroacetone (HTTA) have been shown to exhibit a synergistic effect on the extraction of uranyl ion. The effects of the addition to the organic phase of K-5, K22DD, and tert-butylcyclohexyl-15-crown-5 (15-C-5) on the extraction of UO2 +2 by HTTA in chloroform from 0.5 M NaNO3 at 25°C have been measured. The results indicate the extraction is enhanced by the formation of an adduct, UO2(TTA)2S for K-5 and K22DD. No enhancement of the extraction was seen with the crown ether. The organic phase stability constants for both K-5 and K22DD were evaluated and found to be similar in magnitude. These results suggest that the major factor in the formation of the synergistic adduct is the presence of the nitrogen atom in the synergist. 相似文献
43.
为了确定雷64块S3中储层沉积体系,采用薄片鉴定、重矿物鉴定等手段,对目的层砂岩碎屑母岩类型及物源特征进行了分析;综合录井资料、测井资料对目的层进行地层对比划分,分析了储层的空间展布;综合岩石特征、电学特征对单井的目的层沉积相进行分析。研究表明,雷64块S3中储层为重力流环境的水下扇沉积体系。 相似文献
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Dr. Thomas Le Bihan Dr. Cathryn H. S. Driver Dr. Thomas Ebenhan Dr. Nathalie Le Bris Dr. Jan Rijn Zeevaart Prof. Dr. Raphaël Tripier 《ChemMedChem》2021,16(5):809-821
An improved glucose-chelator-albumin bioconjugate (GluCAB) derivative, GluCAB-2Mal, has been synthesized and studied for in vivo 64Cu-PET/CT imaging in breast cancer mice models together with its first-generation analogue GluCAB-1Mal. The radioligand works on the principle of tumor targeting through the enhanced permeability and retention (EPR) effect with a supportive role played by glucose metabolism. [64Cu]Cu-GluCAB-2Mal (99 % RCP) exhibited high serum stability with immediate binding to serum proteins. In vivo experiments for comparison between tumor targeting of [64Cu]Cu-GluCAB-2Mal and previous-generation [64Cu]Cu-GluCAB-1Mal encompassed microPET/CT imaging and biodistribution analysis in an allograft E0771 breast cancer mouse model. Tumor uptake of [64Cu]Cu-GluCAB-2Mal was clearly evident with twice as much accumulation as compared to its predecessor and a tumor/muscle ratio of up to 5 after 24 h. Further comparison indicated a decrease in liver accumulation for [64Cu]Cu-Glu-CAB-2Mal. 相似文献
46.
在简要介绍HD64F/ 3687芯片的结构及特点的基础上, 将此种芯片应用于低成本变频器中, 使用其内部定时器通过软件生成所需的SPWM波形并由此探讨了HD64F/3687在变频调速中的应用。此芯片在变频调速系统中方便易用,具有可简化硬件电路,降低变频器生产成本等优点。 相似文献
47.
迟洁茹 《青岛大学学报(工程技术版)》2002,17(3):62-64
在TCP/IP协议上 ,定制一套SMTP、POP3、ADDRESSBOOK协议 ,从而实现了定制的电子邮件收发系统 相似文献
48.
该文论述了在Alpha系列计算机以及COSIX64操作系统平台下,开发基于EISAISA总线专用板的驱动程序的技术路线、技术难点及其解决方法。总结了开发COSIX64驱动程序的一般步骤。 相似文献
49.
首先简单介绍了一些高速数据采集方法的优缺点。然后简单介绍了ATMEL公司生产的32位ARMRISC处理器AT91SAM7S64的结构与特点,并利用AT91SAM7S64的ADC和PDC实现90E卷接机组中CIS(烟支检测系统)的高速数据采集。给出了硬件连接图与相关的程序。 相似文献
50.
ATM传输是宽带综合业务数字网的重要技术,为使DSP能接入ATM系统,利用TMS320C64x特有的UTOPIA接口构建了一个ATM系统的从设备.介绍了UTOPIA接口基本的发送和接收操作流程,设计了与主控制器MPC8260连接的接口电路,重点探讨了UTOPIA从设备端的参数设置要点,并给出部分程序段代码. 相似文献