Varghese Beena, Suliman FakhrEldin O, Al-Hajri Aalia, Al Bishri Nahed Surur S, Al-Rwashda Nathir
Department of Chemistry, College of Science, Sultan Qaboos University, Box 36, Al-khod 123, Oman.
Department of Chemistry, College of Science, Sultan Qaboos University, Box 36, Al-khod 123, Oman.
Spectrochim Acta A Mol Biomol Spectrosc. 2018 Feb 5;190:392-401. doi: 10.1016/j.saa.2017.09.060. Epub 2017 Sep 21.
The inclusion complexes of sulfamethoxazole (SMX) with β-cyclodextrin (βCD) and (2-hydroxypropyl) β-cyclodextrin (HPβCD) were prepared. Fluorescence spectroscopy and electrospray mass spectrometry, ESI-MS, were used to investigate and characterize the inclusion complexation of SMX with cyclodextrins in solutions. Whereas in the solid state the complexes were characterized by Fourier transform infrared spectroscopy (FTIR), powder X-ray diffraction (PXRD) and Raman techniques. Enhanced twisted intramolecular charge transfer (TICT), emission as well as local excited (LE) bands were observed upon addition of HPβCD indicate that SMX enters deeper into the cyclodextrins cavity. The stoichiometries and association constants of these complexes have been determined by monitoring the fluorescence data. The effect of presence of ternary components like arginine and cysteine on the complexation efficiency of SMX with cyclodextrins was investigated. Molecular Dynamic simulations were also performed to shed an atomistic insight into the complexation mechanism. The results obtained showed that complexes of SMX with both cyclodextrins are stabilized in aqueous media by strong hydrogen bonding interactions.
制备了磺胺甲恶唑（SMX）与β-环糊精（βCD）和（2-羟丙基）β-环糊精（HPβCD）的包合物。采用荧光光谱法和电喷雾质谱法（ESI-MS）研究并表征了溶液中SMX与环糊精的包合作用。而在固态下，通过傅里叶变换红外光谱（FTIR）、粉末X射线衍射（PXRD）和拉曼技术对复合物进行表征。加入HPβCD后观察到增强的扭曲分子内电荷转移（TICT）、发射以及局部激发（LE）带，表明SMX更深地进入环糊精空腔。通过监测荧光数据确定了这些复合物的化学计量比和缔合常数。研究了精氨酸和半胱氨酸等三元组分的存在对SMX与环糊精包合效率的影响。还进行了分子动力学模拟，以深入了解包合机制的原子水平情况。所得结果表明，SMX与两种环糊精的复合物在水性介质中通过强氢键相互作用得以稳定。
