This work combines, for the first time, 3D-printing technology and a highly efficient metal organic framework (Ca-MOF) as an electrode modifier to produce a novel fully integrated lab-in-a-syringe device for the sensitive determination of Hg(II) by anodic stripping voltammetry. The specific Ca-MOF ([Ca(H₄L)(DMA)₂]·2DMA where H₆L is the N,N’-bis(2,4-dicarboxyphenyl)-oxalamide and DMA is the N,N-dimethylacetamide) shows an exceptional Hg(II) sorption capability over a wide pH range and its mechanism is elucidated via spectroscopic and X-ray diffraction studies. The voltammetric lab-in-a-syringe device is fabricated through a single-step process using a dual extruder 3D printer and is composed of a vessel integrating two thermoplastic conductive electrodes (serving as the counter and pseudo-reference electrodes) and of a small detachable 3D-printed syringe loaded with a graphite paste/Ca-MOF mixture (which serves as the working electrode). After optimization of the fabrication and operational variables, a limit of detection of 0.6 μg L⁻¹ Hg(II) was achieved, which is comparable or lower than that of existing sensors (plastic 3D-printed, gold and MOF-based electrodes). The adoption of 3D printing technology in combination with the highly efficient Ca-MOF enables the fabrication of a simple, low-cost and sensitive electrochemical sensor for Hg(II), which is suitable for on-site applications.

这项工作首次将3D打印技术与高效金属有机骨架（Ca-MOF）作为电极改性剂相结合，以生产出一种新型的完全集成的实验室用注射器设备，用于灵敏地测定Hg（ II）通过阳极溶出伏安法。特定的Ca-MOF（[Ca（H ₄ L）（DMA）₂ ]· 2DMA ，其中H ₆ L是N，N'-双（2,4-二羧基苯基）-草酰胺，DMA是N，N-二甲基乙酰胺）在很宽的pH范围内显示出卓越的Hg（II）吸附能力，其机理已通过光谱和X射线衍射研究得以阐明。使用双挤出机3D打印机通过一步法制造伏安式注射器的装置，它由一个装有两个热塑性导电电极（用作对向电极和伪参比电极）的容器组成，该容器很小装有石墨糊/ Ca-MOF混合物（用作工作电极）的可拆卸3D打印注射器。优化制造和操作变量后，检出限为0.6μgL ^-1汞（II）的含量与现有传感器（塑料3D打印，金和基于MOF的电极）相当或更低。通过将3D打印技术与高效的Ca-MOF结合使用，可以制造适用于现场应用的简单，低成本且灵敏的Hg（II）电化学传感器。