The direct on-site detection of illegal additives in unprocessed food samples is usually a great challenge for electrochemical sensors because of electrode biofouling. In this work, a simple filtration method for the scalable fabrication of disposable single-walled carbon nanotubes (SWCNTs)-based antifouling electrochemical sensors is reported. This method employs flash foam stamp-assisted polydimethylsiloxane (PDMS) patterns to control the region-selective deposition of SWCNTs on polyvinylidene fluoride (PVDF) membranes during filtration, which enables the scalable fabrication of a SWCNTs three-electrode-based sensor with high conductivity, good reproducibility and excellent flexibility. The resulting SWCNTs sensor exhibits a sensitive response towards morphine with a calibration range of 0.2 ∼ 100 μg mL⁻¹ and a detection limit of 0.06 μg mL⁻¹ (S/N = 3). Moreover, probably owing to its unique nanoporous structure, this SWCNTs sensor possesses apparently improved antifouling ability as compared with the widely used glassy carbon electrode (GCE), and allows the direct detection of morphine in unprocessed complex foods such as milk and coffee. The present work thus establishes a simple approach to the scalable production of self-designed SWCNTs electrode arrays suitable for on-site food analysis, which may also provide an alternative to commercial screen-printed carbon electrodes (SPCEs) for electrochemical sensing applications.

由于电极生物污染，直接现场检测未加工食品样品中的非法添加剂通常是电化学传感器的一大挑战。在这项工作中，报道了一种简单的过滤方法，用于可扩展地制造基于一次性单壁碳纳米管 (SWCNT) 的防污电化学传感器。该方法采用快速泡沫印章辅助的聚二甲基硅氧烷 (PDMS) 图案来控制过滤过程中 SWCNT 在聚偏二氟乙烯 (PVDF) 膜上的区域选择性沉积，从而能够可扩展地制造具有高电导率的 SWCNT 三电极传感器，良好的重现性和出色的柔韧性。由此产生的 SWCNTs 传感器对吗啡表现出灵敏的响应，校准范围为 0.2 ∼ 100 μg mL ^-1检测限为 0.06 μg mL ^-1 (S/N = 3)。此外，可能由于其独特的纳米多孔结构，这种 SWCNTs 传感器与广泛使用的玻璃碳电极 (GCE) 相比具有明显提高的防污能力，并且可以直接检测牛奶和咖啡等未加工的复杂食品中的吗啡。因此，本工作建立了一种简单的方法来大规模生产适用于现场食品分析的自行设计的 SWCNT 电极阵列，这也可以为电化学传感应用提供商业丝网印刷碳电极 (SPCE) 的替代方案。