The thermal stability of the monosubstituted cationic cyclodextrin (CD) derivatives PEMEDA-β-CD and PEMPDA-β-CD, which differ in their substituent linker length (ethylene and propylene, respectively), was studied via 1H NMR experiments. PEMPDA-β-CD exhibited higher resistance towards the Hofmann degradation and was chosen as a more suitable host molecule for further studies. Inclusion properties of PEMPDA-β-CD in solution with a series of simple aromatic guests (salicylic acid, p-methoxyphenol and p-nitroaniline) were determined by isothermal titration calorimetry (ITC) and compared to the native β-CD. Permanently charged cationic CD derivatives were successfully deposited on the anionic solid surface of polymeric Nafion® 117 membrane via electrostatic interactions. Deposition kinetics and coverage of the surface were determined by ELSD. Finally, the ability of the CD derivatives bound to the solid surface to encapsulate aromatic compounds from aqueous solution was measured by UV–vis spectroscopy. The obtained results are promising for future industrial applications of the monosubstituted β-CD derivatives, because the preparation of cationic CD derivatives is applicable in large scale, without the need of chromatographic purification. Their ionic deposition on a solid surface is simple, yet robust and a straightforward process as well.
通过
1H NMR实验研究了单取代阳离子
环糊精(CD)衍
生物P
EME
DA-β-CD和P
EMPDA-β-CD的热稳定性,它们在取代基连接物长度(分别为
乙烯和
丙烯)上有所不同。P
EMPDA-β-CD对Hofmann降解表现出更高的抗性,被选为更适合进行进一步研究的宿主分子。通过等温滴定量热法(ITC)测定了P
EMPDA-β-CD在溶液中与一系列简单芳香客体(
水杨酸、
p-
甲氧基苯酚和
p-
硝基苯胺)的包含性能,并与天然β-CD进行了比较。永久带电的阳离子CD衍
生物通过静电相互作用成功沉积在聚合物Nafion® 117膜的阴离子固体表面上。通过EL
SD确定了沉积动力学和表面覆盖度。最后,通过UV–vis光谱测量了CD衍
生物绑定在固体表面上从
水溶液中封装芳香化合物的能力。得到的结果对于单取代β-CD衍
生物未来工业应用是有希望的,因为阳离子CD衍
生物的制备可在大规模应用中进行,无需色谱纯化。它们在固体表面的离子沉积是简单、稳健且直接的过程。