Department of Analytical Chemistry, Physical Chemistry and Chemical Engineering, Faculty of Sciences, University of Alcalá, E-28871 Alcalá de Henares, Madrid, Spain.
Faculty of Bioscience and Technology for Food, Agriculture and Environment, University of Teramo, Campus "Aurelio Saliceti" via R. Balzarini 1, 64100 Teramo, Italy.
Anal Chem. 2020 Oct 6;92(19):13565-13572. doi: 10.1021/acs.analchem.0c03240. Epub 2020 Sep 15.
A novel benchtop approach to fabricate xurography-enabled thermally transferred (XTT) carbon nanomaterial-based electrochemical sensors is proposed. Filtered nanomaterial (NM) films were transferred from Teflon filters to polyethylene terephthalate-ethylene vinyl acetate (PET-EVA) substrates by a temperature-driven approach. Customized PET-EVA components were xurographically patterned by a cutting plotter. The smart design of PET-EVA films enabled us to selectively transfer the nanomaterial to the exposed EVA side of the substrate. Hence, the substrate played an active role in selectively controlling where nanomaterial transfer occurred allowing us to design different working electrode geometries. Counter and reference electrodes were integrated by a stencil-printing approach, and the whole device was assembled by thermal lamination. To prove the versatility of the technology, XTT materials were exclusively made of carbon black (XTT-CB), multiwalled carbon nanotubes (XTT-MWCNTs), and single-walled carbon nanotubes (XTT-SWCNTs). Their electrochemical behavior was carefully studied and was found to be highly dependent on the amount and type of NM employed. XTT-SWCNTs were demonstrated to be the best-performing sensors, and they were employed for the determination of l-tyrosine (l-Tyr) in human plasma from tyrosinemia-diagnosed patients. High analytical performance toward l-Tyr (linear range of 0.5-100 μM, LOD = 0.1 μM), interelectrode precision (RSD = 3%, = 10; RSD calibration slope = 4%, = 3), and accurate l-Tyr quantification in plasma samples with low relative errors (≤7%) compared to the clinical declared values were obtained. The proposed benchtop approach is cost-effective and straightforward, does not require sophisticated facilities, and can be potentially employed to develop pure or hybrid nanomaterial-based electrodes.
提出了一种新颖的台式方法来制造用于热传递（XTT）的碳纳米材料电化学传感器。通过温度驱动的方法，将过滤的纳米材料（NM）薄膜从聚四氟乙烯（PTFE）过滤器转移到聚对苯二甲酸乙二醇酯-乙烯-醋酸乙烯酯（PET-EVA）基底上。通过切割绘图仪对定制的 PET-EVA 组件进行 xurography 图案化。PET-EVA 薄膜的智能设计使我们能够选择性地将纳米材料转移到基底的暴露 EVA 侧。因此，基底在选择性控制纳米材料转移发生的位置方面发挥了积极作用，使我们能够设计不同的工作电极几何形状。通过模板印刷方法集成了对电极和参比电极，并且整个装置通过热压层压进行组装。为了证明该技术的多功能性，仅使用碳黑（XTT-CB）、多壁碳纳米管（XTT-MWCNTs）和单壁碳纳米管（XTT-SWCNTs）制成 XTT 材料。仔细研究了它们的电化学行为，发现其高度依赖于所使用的 NM 的数量和类型。XTT-SWCNTs 被证明是性能最佳的传感器，并将其用于从酪氨酸血症诊断患者的人血浆中测定 l-酪氨酸（l-Tyr）。对 l-Tyr 具有高分析性能（线性范围为 0.5-100 μM，LOD = 0.1 μM），电极间精度（RSD = 3%，n = 10；RSD 校准斜率 = 4%，n = 3），以及与临床声明值相比，血浆样品中 l-Tyr 的定量结果具有低相对误差（≤7%）。所提出的台式方法具有成本效益且简单直接，不需要复杂的设备，并且可以潜在地用于开发纯或混合纳米材料基电极。
