It is of great significance to develop versatile and cost-effective point-of-care testing (POCT) systems for simultaneous quantitation of multiple analytes on-site. This work reports on: 1) the customized electrodes which exhibit good analytical performance for simultaneous detection of Cd²⁺, Cu²⁺, Hg²⁺, Pb²⁺ with low detection limits (Cd²⁺, 0.296 μM; Cu²⁺, 0.055 μM; Hg²⁺, 0.351 μM; and Pb²⁺, 0.025 μM) and wide dynamic ranges (Cd²⁺, 0.50-12.5 μM; Cu²⁺, 0.10-9.50 μM; Hg²⁺, 0.50-12.5 μM; and Pb²⁺, 0.10-12.5 μM) using differential pulse voltammetry (DPV) measurements. 2) a hand-held electrochemical analyzer which can realize two-way communication with a smartphone and implement DPV measurements; its cost, weight and power consumption are ∼$10.0, ∼30 g and ∼253 mW, respectively; 3) a self-developed APP DHMI which can control the analyzer, receive data from the analyzer, and plot the voltammograms on smartphone’s screen in real-time. This quantitative POCT system has been successfully demonstrated for simultaneous quantitation of Cd²⁺, Cu²⁺, Hg²⁺, Pb²⁺ in tap water, mineral water and Pearl River water, and the quantitation results correlated well with ICP-MS measurements. The features of cost-effectiveness, ease-to-use and reliability make this quantitative POCT system useful for on-site monitoring of multiple heavy metal ions, especially in resource-constrained environments.

开发多功能且具有成本效益的即时检验（POCT）系统对现场同时分析多种分析物具有重要意义。这项工作报告：1）定制的电极，具有良好的分析性能，可同时检测Cd 2 ⁺，Cu 2 ⁺，Hg 2 ⁺，Pb ²⁺且检测限低（Cd 2 ⁺，0.296μM; Cu ²⁺， 0.055μM;汞²⁺，0.351μM;和Pb ²⁺，0.025μM）和宽动态范围（CD ²⁺，0.50-12.5μM;铜²⁺，0.10-9.50μM;汞²⁺，0.50-12.5μM;和Pb ²⁺（0.10-12.5μM），使用差分脉冲伏安法（DPV）测量。2）手持式电化学分析仪，可以与智能手机实现双向通讯并实现DPV测量；它的成本，重量和功耗分别为约10.0美元，约30 g和约253 mW；3）自行开发的APP DHMI，可以控制分析仪，从分析仪接收数据，并在智能手机的屏幕上实时绘制伏安图。该定量POCT系统已成功证明可同时定量Cd 2 ⁺，Cu 2 ⁺，Hg 2 ⁺，Pb ²⁺在自来水，矿泉水和珠江水中进行定量分析，定量结果与ICP-MS很好地相关。具有成本效益，易于使用和可靠性的特点，使得该定量POCT系统可用于现场监测多种重金属离子，特别是在资源有限的环境中。