This work is focused on the synthesis and optical properties of cone-shaped structural feature di-dendron polyamidoamine dendrimers up to the third generation with mono-Boc-protected ethylenediamine (EDA) as a core. Strong UV absorbance spectra and fluorescence spectra from di-dendron dendrimers with different terminal groups (-NH2, -COOCH3) were studied under different conditions by varying experimental parameters such as concentration and pH. The optical density and fluorescence intensities increased when di-dendron dendrimers generation number increased from 0.5 to 3.0. It was confirmed that the concentration of di-dendron dendrimers plays an important role in fluorescence intensity. The increase in fluorescence intensity was linear in low concentration regions, but the intensity increased slowly in high concentration regions. The results also showed a rapid increase in fluorescence intensity at low pH. The formation of a fluorescence-emitting moiety had a close relationship to protonated tertiary amine groups in di-dendron dendrimers derived from mono-Boc-protected EDA cores. Furthermore, the formation of fluorescent chemical species was irreversible. Copyright © 2010 John Wiley & Sons, Ltd.
这项工作聚焦于以单Boc保护的
乙二胺(E
DA)作为核心的圆锥形结构特征二树枝聚酰胺树枝状聚合物的合成和光学性质,研究至第三代。研究了不同末端基团(-NH2,-COOCH3)的二树枝聚合物在不同条件下的强紫外吸收光谱和荧光光谱,通过改变实验参数如浓度和pH进行研究。随着二树枝聚合物的代数从0.5增加到3.0,光学密度和荧光强度均有所增加。确认了二树枝聚合物的浓度在荧光强度中起重要作用。荧光强度在低浓度区呈线性增加,但在高浓度区增加缓慢。结果还显示,在低pH下荧光强度快速增加。荧光发射部分的形成与来源于单Boc保护E
DA核心的二树枝聚合物中的质子化三级胺基团有密切关系。此外,荧光
化学物种的形成是不可逆的。版权 © 2010 John Wiley & Sons, Ltd.