Changzhou Maternal and Child Health Care Hospital, Nanjing Medical University, Changzhou, 214221, China; Jiangsu Key Laboratory of Advanced Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, China.
Jiangsu Key Laboratory of Advanced Materials and Technology, School of Petrochemical Engineering, Changzhou University, Changzhou, 213164, China.
Anal Chim Acta. 2022 May 8;1206:339810. doi: 10.1016/j.aca.2022.339810. Epub 2022 Apr 4.
In most cases, the recognition efficiency of chiral electroanalysis relies on the chiral carbon center, whereas its medium is just used to transfer the electron. Differently, in this study, an ionic helical polymer with right- or left-handed configuration was prepared via an acid-base interaction between the ionic polymer and enantiopure 1,2-diphenylethane-1,2-diamine. The structure and absolute handedness of the helical polymers were well characterized by the circular dichroism spectrum, gel permeation chromatography, and Fourier transform infrared spectroscopy. The pyridinium moiety of the helical polymer contributes to the electron transfer when it was directly modified on the surface of the glassy carbon electrode as an electrochemical enantioselector for chiral electroanalysis. Results indicated that different configurations of amino acids can be recognized in the responses of different electric signals, namely peak current or peak potential. The peak current ratio between L- and d-isomer can be up to 7.5 and 23.2 for tryptophan and tyrosine, respectively. Most importantly, the reversal of the electric signal can be observed toward L- and d-isomer under the different testing conditions such as pH and metal ion content, because of two stereogenic centers (the chiral inducer and the stereogenic axis) in the helical polymer. Overall, we believe that the present study offers a great promise for the synthesis and application of the ionic helical polymers accompanying with multiple stereogenic centers.
在大多数情况下，手性电化学分析的识别效率依赖于手性碳原子，而其介质仅用于传递电子。与此不同的是，在本研究中，通过离子聚合物与对映纯 1,2-二苯基乙烷-1,2-二胺之间的酸碱相互作用，制备了具有右手或左手构型的离子螺旋聚合物。通过圆二色光谱、凝胶渗透色谱和傅里叶变换红外光谱对螺旋聚合物的结构和绝对手性进行了很好的表征。当螺旋聚合物的吡啶部分直接修饰在玻璃碳电极表面作为手性电化学分析的电化学对映体选择剂时，它有助于电子转移。结果表明，在不同的电信号响应中，可以识别出不同构型的氨基酸，即峰电流或峰电位。色氨酸和酪氨酸的 L-和 d-异构体的峰电流比分别高达 7.5 和 23.2。最重要的是，由于螺旋聚合物中存在两个手性中心（手性诱导剂和手性轴），在不同的测试条件下，如 pH 值和金属离子含量，可以观察到电信号的反转，即 L-和 d-异构体。总的来说，我们相信本研究在手性离子聚合物的合成和应用方面提供了很大的前景，同时伴随着多个手性中心。
