Nanoscale Carbonate Ion-Selective Amperometric/Voltammetric Probes Based on Ion–Ionophore Recognition at the Organic/Water Interface: Hidden Pieces of the Puzzle in the Nanoscale Phase
Nanoscale Carbonate Ion-Selective Amperometric/Voltammetric Probes Based on Ion–Ionophore Recognition at the Organic/Water Interface: Hidden Pieces of the Puzzle in the Nanoscale Phase
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基于有机/水界面离子-离子载体识别的纳米级碳酸盐离子选择性电流/伏安探针：纳米级阶段谜题的隐藏部分
DOI：
10.1021/acs.analchem.2c02626
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发表时间：
2023
影响因子：
7.4
通讯作者：
Kim, Jiyeon
中科院分区：
文献类型：
--
作者：
Elangovan, Subhashini;Puri, Surendra Raj;Madawala, Hiranya;Pantano, Justin;Pellock, Brett;Kiesewetter, Matthew K.;Kim, Jiyeon
在这里，我们报道了基于促进离子转移(IT)的碳酸盐(CO32-)离子选择性安培/伏安纳米探针在两个不相容的电解质溶液之间的纳米界面上的成功展示和应用。这项电化学研究揭示了使用广泛可用的西蒙型离子载体与CO32-形成共价键来控制CO32-选择性纳米探针的关键因素，即亲脂性离子载体在有机相中的缓慢溶解，水合离子载体的激活，界面附近水合离子-离子载体络合物的特殊溶解性，以及纳米界面的清洁度。这些因素通过纳米管伏安法得到了实验证实，在纳米管中填充了含有三氟苯乙酮衍生物CO32-离子载体(CO32-离子载体VII)的有机相，通过伏安法和安培法检测水中的CO32-，研究了促进的CO32-IT。对可重复伏安数据的理论评估证实，CO32-离子载体VII促进ITS(FITS)的动力学遵循界面ITS过程中由水指形成/解离和离子-离子载体络合/解离共同控制的一步电化学(E)机制。得到的速率常数k0=0.048 cm/S，与报道的利用离子载体与离子形成非共价键的其他FIT反应的值非常相似，这意味着CO32-离子-离子载体之间的弱结合使我们能够用快速纳米管伏安法观察FITS，而不考虑离子和离子载体之间的键合性质。通过测量金属还原细菌白氏杆菌MR-1在各种干扰因素如H_2PO_4~-、Cl~-和SO_4~(2-)存在下，在细菌生长介质中有机燃料氧化产生的CO_(32-)浓度，进一步证明了选择性安培纳米探针的分析用途。
Here, we report on the successful demonstration and application of carbonate (CO32–) ion-selective amperometric/voltammetric nanoprobes based on facilitated ion transfer (IT) at the nanoscale interface between two immiscible electrolyte solutions. This electrochemical study reveals critical factors to govern CO32–-selective nanoprobes using broadly available Simon-type ionophores forming a covalent bond with CO32–, i.e., slow dissolution of lipophilic ionophores in the organic phase, activation of hydrated ionophores, peculiar solubility of a hydrated ion–ionophore complex near the interface, and cleanness at the nanoscale interface. These factors are experimentally confirmed by nanopipet voltammetry, where a facilitated CO32–IT is studied with a nanopipet filled with an organic phase containing the trifluoroacetophenone derivative CO32–ionophore (CO32–ionophore VII) by voltammetrically and amperometrically sensing CO32–in water. Theoretical assessments of reproducible voltammetric data confirm that the dynamics of CO32–ionophore VII-facilitated ITs (FITs) follows the one-step electrochemical (E) mechanism controlled by both water-finger formation/dissociation and ion–ionophore complexation/dissociation during interfacial ITs. The yielded rate constant,k0= 0.048 cm/s, is very similar to the reported values of other FIT reactions using ionophores forming non-covalent bonds with ions, implying that a weak binding between CO32–ion–ionophore enables us to observe FITs by fast nanopipet voltammetry regardless of the nature of bondings between the ion and ionophore. The analytical utility of CO32–-selective amperometric nanoprobes is further demonstrated by measuring the CO32–concentration produced by metal-reducing bacteriaShewanella oneidensisMR-1 as a result of organic fuel oxidation in bacterial growth media in the presence of various interferents such as H2PO4–, Cl–, and SO42–.