College of Sciences, Northeastern University, Shenyang, 110819, China.
College of Sciences, Northeastern University, Shenyang, 110819, China.
Anal Chim Acta. 2024 Sep 15;1322:342995. doi: 10.1016/j.aca.2024.342995. Epub 2024 Jul 25.
Chirality, an inherent characteristic of natural substances (such as sugars, peptides, proteins, and nucleic acid), plays a vital role in human metabolism and exerts substantial impacts. In general, chiral drugs can display diverse pharmacological and pharmacokinetic properties. One enantiomer may exhibit therapeutic effects, while the other could cause adverse reactions. Selective recognition of enantiomers is thus a significant task in the biomolecular and pharmaceutical fields. Despite the development of several chiral identification techniques, low-cost enantioselective sensing methods remain highly desirable. Here, we designed and developed an electrochemical sensing device for reductive enantiomer identification using natural wood channels as the substrate. The wood channels were endowed with oxidase-like activity through the in-situ growth of cerium oxide nanoparticles (CeO). Chiral recognition capability was further introduced by incorporating a layer of chiral ZIF-8 (L-ZIF) as the chiral selector. To demonstrate the enantioselective sensing performance, 3,4-dihydroxyphenylalanine (DOPA) enantiomers were employed as model analytes. Due to the oxidase-like activity and the confinement effect of the proposed channels, the captured DOPA enantiomers were effectively oxidized to their quinone structure, and the Ce(IV) in CeO was reduced to Ce(III). These changes led to alterations in the surface charge of the channels, thereby modulating their ionic transport properties. This sensing mechanism also proved useful for the identification of other reductive enantiomers. The limits of detection for l-DOPA and d-DOPA were determined as 2.41 nM and 1.56 nM, respectively. The resulting wood channel-based sensing device not only can be used for the recognition and detection of reductive enantiomers, but also is expected to be applied to the non-electochemically active substances. Moreover, this study offers a novel type of solid-state channel material with low cost, reproducibility, and easy accessibility for electrochemical chiral sensing.
手性是天然物质（如糖、肽、蛋白质和核酸）的固有特征，在人类代谢中起着至关重要的作用，并产生巨大的影响。一般来说，手性药物可能表现出不同的药理和药代动力学特性。一种对映异构体可能具有治疗效果，而另一种可能引起不良反应。因此，对映异构体的选择性识别是生物分子和制药领域的一项重要任务。尽管已经开发出了几种手性识别技术，但仍然需要开发低成本的对映体选择性传感方法。在这里，我们设计并开发了一种基于天然木材通道作为基底的电化学传感装置，用于还原型对映异构体的识别。通过原位生长氧化铈纳米粒子（CeO），木材通道被赋予了氧化酶样的活性。通过引入一层手性 ZIF-8（L-ZIF）作为手性选择剂，进一步引入了手性识别能力。为了证明手性识别性能，我们使用 3,4-二羟基苯丙氨酸（DOPA）对映异构体作为模型分析物。由于氧化酶样活性和所提出的通道的限制效应，捕获的 DOPA 对映异构体被有效地氧化为醌结构，CeO 中的 Ce(IV)被还原为 Ce(III)。这些变化导致通道表面电荷发生变化，从而调节其离子传输特性。这种传感机制也可用于识别其他还原型对映异构体。l-DOPA 和 d-DOPA 的检测限分别确定为 2.41 nM 和 1.56 nM。基于木材通道的传感装置不仅可用于还原型对映异构体的识别和检测，而且有望应用于非电化学活性物质。此外，本研究为电化学手性传感提供了一种新型的低成本、可重复使用且易于获得的固态通道材料。
