Generational, skeletal and substitutional diversities in generation one poly (amidoamine) dendrimers
Generational, skeletal and substitutional diversities in generation one poly (amidoamine) dendrimers
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DOI：
10.1016/j.polymer.2005.01.081
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发表时间：
2005-04-15
期刊：
影响因子：
4.6
通讯作者：
Balogh, LP
中科院分区：
文献类型：
--
作者：
Shi, XY;Bányai, I;Balogh, LP
乙二胺核聚酰胺-胺（PAMAM）树枝状大分子及其衍生物的结构偏差可以定义为骨架和/或取代二聚体。详细分析树枝状聚合物起始材料和衍生物是必要的，以了解商业树枝状聚合物材料的固有特性及其与后续表面改性相关的变化。在本文中，乙二胺核心一代PAMAM树枝状大分子（PAMAM_E1或E1）的结构偏差进行了研究和确定的框架下，系统的调查，使用组合表征技术。使用第1代伯胺封端的PAMAM树枝状聚合物（E1.NH2）作为起始材料来合成缩水甘油（E1.N（Gly）OH）和乙酰胺封端的树枝状聚合物（E1.NHAc）。采用聚丙烯酰胺凝胶电泳（PAGE）、毛细管电泳（CE）、凝胶渗透色谱（GPC）、酸碱滴定、核磁共振（NMR）、基质辅助激光解吸电离飞行时间（MALDI-TOF）和电喷雾电离（ESI）质谱等方法对产物的纯度和均一性进行了表征。PAGE和CE研究表明，在pH2.5时，电泳迁移率顺序为E1.NH2 > E1.N（Gly）OH > E1.NHAc。质谱和NMR研究（H-1、C-13 DEPT-135和C-13 NMR、COSY、HETCOR、NOESY）表明（a）所研究的EI树枝状聚合物是世代纯的，（B）E1. NHAc和E1. N（Gly）OH树枝状聚合物，并且基本上具有与E1. NH 2相同的缺陷和骨架多样性。E1.N（Gly）OH的CE电泳图中主峰的宽分布表明E1.NH2的不完全羟基化导致树枝状聚合物分子之间的额外取代多样性。电位滴定研究证明，末端和叔胺基团的总数也偏离理论值。核磁共振波谱法用于定性和定量分析树枝状大分子及其衍生物的结构缺陷。E1.NH2和E1.NHAc仅显示出与理想结构的微小偏差，并且分别显示出窄的分布;而E1.N（Gly）OH具有以14 +/- 3个缩水甘油取代基为中心的更宽的分布。第1代PAMAMs的结构变化的研究提供了新的见解的表征更高一代PAMAM树枝状聚合物和衍生物的骨架偏差以及其他由此产生的diligence相关的树枝状聚合物表面官能化。(c)2005爱思唯尔有限公司保留所有权利。
Structural deviations of ethylenediamine core polyamidoamine (PAMAM) dendrimers and derivatives can be defined as skeletal and/or substitutional diversities. Detailed analysis of dendrimer starting materials and derivatives is necessary to understand the intrinsic characteristics of commercial dendrimer materials and their variations related to subsequent surface modifications. In this paper, structural deviations of ethylenediamine core generation 1 PAMAM dendrimers (PAMAM_E1 or E1) are studied and determined in a frame of a systematic investigation using combined characterization techniques. A primary amine-terminated PAMAM dendrimer of generation 1 (E1.NH2) was used as a starting material to synthesize glycidol (E1.N(Gly)OH) and acetamide-terminated (E1.NHAc) dendrimers. The purity and homogeneity of these dendrimers were extensively characterized by polyacrylamide gel electrophoresis (PAGE), capillary electrophoresis (CE), gel permeation chromatography (GPC), acid-base titration, nuclear magnetic resonance (NMR), matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) and electrospray ionization (ESI) mass spectrometry. PAGE and CE studies showed that electrophoretic mobilities at pH 2.5 are in the order of E1.NH2 > E1.N(Gly)OH > E1.NHAc. Mass spectrometry and NMR investigations (H-1, C-13 DEPT-135, and C-13 NMR, COSY, HETCOR, NOESY) suggested that (a) the studied E I dendrimers were generationally pure, (b) E1.NHAc and E1.N(Gly)OH dendrimers, and essentially had the same defects and skeletal diversity as E1.NH2 did. The broad distribution of the main peak in the CE electropherogram of E1.N(Gly)OH revealed the incomplete hydroxylation of E1.NH2 resulting in additional substitutional diversity between the dendrimer molecules. Potentiometric titration studies proved that overall numbers of terminal and tertiary amine groups also deviated from the theoretical values. NMR spectroscopy was applied for both qualitative and quantitative analysis of the structural defects of dendrimers and derivatives. E1.NH2 and E1.NHAc exhibited only minor deviations from ideal structures and, respectively, displayed a narrow distribution; while E1.N(Gly)OH had a much broader distribution centered around 14 +/- 3 glycidol substituents. The study of structural variations in generation 1 PAMAMs provides new insights for the characterization of higher generation PAMAM dendrimers and derivatives both in terms of the skeletal deviations as well as other resulting diversities related to dendrimer surface functionalization. (c) 2005 Elsevier Ltd. All rights reserved.