一种锌基-类杯[3]芳烃化合物对氨基葡萄糖的识别

Synthesis of zinc-based calix[3] arene-like compounds for the recognition of glucosamine

设计合成了一种锌基-类杯[3]芳烃化合物Zn-Lg1,实现了对氨基葡萄糖的高灵敏度识别.利用紫外-可见光谱和荧光光谱等研究了Zn-Lg1对氨基葡萄糖的识别过程与机理.紫外-可见光谱表明,向Zn-Lg1中加入氨基葡萄糖后,波长423 nm处的吸收峰下降, 320和281 nm处吸收峰增强,等吸收点为360 nm,说明氨基葡萄糖分子已经进入Zn-Lg1内部,主客体计量比为1∶1,平衡常数为1.6×103L/mol.通过对比研究无磺酰胺基团的类杯[3]芳烃化合物Zn-Lg2对氨基葡萄糖的识别效果,分析了Zn-Lg1中磺酰胺部分的氢键在识别中的作用.荧光光谱表明,向Zn-Lg1中加入氨基葡萄糖后,激发波长为360 nm,发射波长从516 nm略蓝移至513 nm,荧光强度增强,最低检测限达到5.0μmol/L.

A zinc-based calix[3]arene-like compound Zn-Lg1 was designed and synthesized to achieve a high-sensitivity detection of glucosamine.The recognition process and mechanism of glucosamine by ZnLg1 were studied by ultraviolet-visible spectroscopy(UV-vis)and fluorescence spectroscopy.UV-vis spectra showed that the intensity of the absorption peak at 423 nm decreased upon addition of glucosamine to Zn-Lg1,the intensity of the absorption peak at 320 and 281 nm increased.The isobestic point at360 nm was obtained,revealing that glucosamine molecules had entered the inner structure of Zn-Lg1 compound.Titration data gave excellent fits to a 1∶1 binding model between the host and guest,and the equilibrium constant was 1.6×103 L/mol.For comparison and to analyze the effect of hydrogen bonds of the sulfonamide moiety,the other zinc-based calix[3]arene-like compound Zn-Lg2 without sulfonamide groups was synthesized and applied in the recognition of glucosamine.It indicated that the recognition performance of Zn-Lg1 to glucosamine was better than that of Zn-Lg2,due to the sulfonamide groups on Zn-Lg1.Fluorescence spectra showed that the emission wavelength was slightly blue shifted to513 nm from 516 nm with the excitation wavelength of 360 nm after the addition of glucosamine to Zn-Lg1,and the fluorescence intensity increased.The detection limit was up to 5.0μmol/L.