Bene Camille, Laborde Adrian, Légnani Morgan, Flahaut Emmanuel, Launay Jérôme, Temple-Boyer Pierre
CNRS, LAAS, 7 Avenue du Colonel Roche, F-31400 Toulouse, France.
INSAT, UT3-PS, INP, University of Toulouse, 118 Route de Narbonne, CEDEX 9, 31062 Toulouse, France.
Sensors (Basel). 2024 Sep 15;24(18):5994. doi: 10.3390/s24185994.
The development of ISE-based sensors for the analysis of nitrates in liquid phase is described in this work. Focusing on the tetradodecylammonium nitrate (TDDAN) ion exchanger as well as on fluoropolysiloxane (FPSX) polymer-based layers, electrodeposited matrixes containing double-walled carbon nanotubes (DWCNTs), embedded in either polyethylenedioxythiophene (PEDOT) or polypyrrole (PPy) polymers, ensured improved ion-to-electron transducing layers for NO detection. Thus, FPSX-based pNO-ElecCell microsensors exhibited good detection properties (sensitivity up to 55 mV/pX for NO values ranging from 1 to 5) and acceptable selectivity in the presence of the main interferent anions (Cl, HCO, and SO). Focusing on the temporal drift bottleneck, mixed results were obtained. On the one hand, relatively stable measurements and low temporal drifts (~1.5 mV/day) were evidenced on several days. On the other hand, the pNO sensor properties were degraded in the long term, being finally characterized by high response times, low detection sensitivities, and important measurement instabilities. These phenomena were related to the formation of some thin water-based layers at the polymer-metal interface, as well as the physicochemical properties of the TDDAN ion exchanger in the FPSX matrix. However, the improvements obtained thanks to DWCNT-based ion-to-electron transducing layers pave the way for the long-term analysis of NO ions in real water-based solutions.
本文描述了用于液相硝酸盐分析的基于离子选择电极（ISE）的传感器的开发。重点关注硝酸十四烷基铵（TDDAN）离子交换剂以及含氟聚硅氧烷（FPSX）聚合物基涂层，嵌入聚乙撑二氧噻吩（PEDOT）或聚吡咯（PPy）聚合物中的含有双壁碳纳米管（DWCNT）的电沉积基质确保了用于NO检测的改进的离子-电子转换层。因此，基于FPSX的pNO-ElecCell微传感器表现出良好的检测性能（对于1至5的NO值，灵敏度高达55 mV/pX），并且在存在主要干扰阴离子（Cl、HCO和SO）的情况下具有可接受的选择性。关注时间漂移瓶颈，得到了混合结果。一方面，在几天内证明了相对稳定的测量和较低的时间漂移（约1.5 mV/天）。另一方面，pNO传感器的性能长期下降，最终表现为响应时间长、检测灵敏度低和测量不稳定。这些现象与聚合物-金属界面处一些薄水基层的形成以及FPSX基质中TDDAN离子交换剂的物理化学性质有关。然而，基于DWCNT的离子-电子转换层所取得的改进为在实际水基溶液中对NO离子进行长期分析铺平了道路。
