Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, United States.
Department of Chemistry, Colorado State University, Fort Collins, CO, 80523, United States; Access Sensor Technologies, Fort Collins, CO, 80526, United States.
Anal Chim Acta. 2020 Mar 22;1103:58-66. doi: 10.1016/j.aca.2019.12.047. Epub 2019 Dec 31.
Cadmium (Cd) and lead (Pb) pollution is a significant environmental and human health concern, and methods to detect Cd and Pb on site are valuable. Stencil-printed carbon electrodes (SPCEs) are an attractive electrode material for point-of-care (POC) applications due to their low cost, ease of fabrication, disposability and portability. At present, SPCEs are exclusively formulated from graphitic carbon powder and conductive carbon ink. However, graphitic carbon SPCEs are not ideal for heavy metal sensing due to the heterogeneity of graphitic SPCE surfaces. Moreover, SPCEs typically require extensive modification to provide desirable detection limits and sensitivity at the POC, significantly increasing cost and complexity of analysis. While there are many examples of chemically modified SPCEs, the bulk SPCE composition has not been studied for heavy metal detection. Here, a glassy carbon microparticle stencil printed electrode (GC-SPE) was developed. The GC-SPEs were first characterized with SEM and cyclic voltammetry and then optimized for Cd and Pb detection with an in situ Bi-film plated. The GC-SPEs require no chemical modification or pretreatment significantly decreasing the cost and complexity of fabrication. The detection limits for Cd and Pb were estimated to be 0.46 μg L and 0.55 μg L, respectively, which are below EPA limits for drinking water (5 μg L Cd and 10 μg L Pb) [1]. The reported GC-SPEs are advantageous with their low cost, ease of fabrication and use, and attractive performance. The GC-SPEs can be used for low-level metal detection at the POC as shown in the report herein.
镉（Cd）和铅（Pb）污染是一个重大的环境和人类健康问题，现场检测 Cd 和 Pb 的方法具有重要价值。模版印刷碳电极（SPCE）由于其低成本、易于制造、可一次性使用和便携性，是一种有吸引力的即时检测（POC）应用电极材料。目前，SPCE 完全由石墨碳粉和导电碳墨制成。然而，由于石墨 SPCE 表面的不均匀性，石墨碳 SPCE 并不适合用于重金属感测。此外，SPCE 通常需要广泛的修饰，以在 POC 提供理想的检测限和灵敏度，这显著增加了分析的成本和复杂性。虽然有许多化学修饰的 SPCE 示例，但尚未研究大块 SPCE 成分用于重金属检测。在这里，开发了一种玻璃碳微球模版印刷电极（GC-SPE）。首先用 SEM 和循环伏安法对 GC-SPE 进行了表征，然后用原位镀 Bi 膜对其进行了优化，用于 Cd 和 Pb 的检测。GC-SPE 无需进行化学修饰或预处理，显著降低了制造成本和复杂性。Cd 和 Pb 的检测限估计分别为 0.46μg L 和 0.55μg L，低于 EPA 规定的饮用水限值（5μg L Cd 和 10μg L Pb）[1]。所报道的 GC-SPE 具有成本低、易于制造和使用以及有吸引力的性能等优点。如本文所述，GC-SPE 可用于 POC 的低水平金属检测。
