College of Pharmacy, Department of Pathology, Weifang Medical University, Weifang, 261053, China.
College of Chemistry, Chemical Engineering and Materials Science, Shandong Normal University, Jinan, 250014, China.
Anal Chim Acta. 2023 Sep 1;1272:341480. doi: 10.1016/j.aca.2023.341480. Epub 2023 Jun 9.
Chirality is an important property of nature and it regulates fundamental phenomena in nature and organisms. Here, we develop a chiral electrochemical sensor based on copper-amino acid mercaptide nanorods (L-CuCys NRs) to discriminate tryptophan (Trp) isomers. The chiral L-CuCys NRs are prepared in alkaline solution based on the facile coordination reaction between the sulfhydryl groups of L-Cys and copper ions. Since the stability constant (K) of L-CuCys NRs with L-Trp (752) are much higher than that of L-CuCys NRs with D-Trp (242), the cross-linking bonds between L-CuCys NRs and L-Trp are more stable than those between L-CuCys NRs and D-Trp. Consequently, this electrochemical sensor can selectively recognize the Trp isomers with an enantiomeric electrochemical difference ratio (I/I) of 3.22, and it exhibits a detection limit of 0.26 μM for L-Trp. Moreover, this electrochemical sensor can quantitatively measure Trp isomers in complex samples. Importantly, this electrochemical sensor has the characteristics of high stability, good repeatability, easy fabrication, low cost, and efficient discrimination of tryptophan (Trp) isomers.
手性是自然界的重要性质，它调控着自然界和生物体内的基本现象。在这里，我们开发了一种基于铜-氨基酸巯基纳米棒（L-CuCys NRs）的手性电化学生物传感器，用于区分色氨酸（Trp）异构体。手性 L-CuCys NRs 是在碱性溶液中通过 L-Cys 上的巯基基团与铜离子之间的简单配位反应制备的。由于 L-CuCys NRs 与 L-Trp（752）的稳定常数（K）远高于 L-CuCys NRs 与 D-Trp（242）的稳定常数，因此 L-CuCys NRs 与 L-Trp 之间的交联键比 L-CuCys NRs 与 D-Trp 之间的交联键更稳定。因此，该电化学生物传感器可以选择性地识别色氨酸异构体，具有 3.22 的对映电化学差异比（I/I），对 L-Trp 的检测限为 0.26 μM。此外，该电化学生物传感器可以定量测量复杂样品中的色氨酸异构体。重要的是，该电化学生物传感器具有高稳定性、良好的重现性、易于制造、低成本和高效区分色氨酸（Trp）异构体的特点。
