Centre for Photonic Devices and Sensors, Department of Engineering , University of Cambridge , Cambridge CB3 0FA , United Kingdom.
Institute of Nano Electronic Engineering , Universiti Malaysia Perlis , Lot 106, 108 & 110, Tingkat 1, Block A, Taman Pertiwi Indah, Jalan Kangar-Alor Setar, Seriab, 01000 Kangar , Perlis , Malaysia.
ACS Sens. 2018 Sep 28;3(9):1756-1764. doi: 10.1021/acssensors.8b00490. Epub 2018 Sep 19.
Heavy metals are highly toxic at trace levels and their pollution has shown great threat to the environment and public health worldwide where current detection methods require expensive instrumentation and laborious operation, which can only be accomplished in centralized laboratories. Herein, we report a low-cost, paper-based microfluidic analytical device (μPAD) for facile, portable, and disposable monitoring of mercury, lead, chromium, nickel, copper, and iron ions. Triple indicators or ligands that contain ions or molecules are preloaded on the μPADs and upon addition of a metal ion, the colorimetric indicators will elicit color changes observed by the naked eyes. The color features were quantitatively analyzed in a three-dimensional space of red, green, and blue or the RGB-space using digital imaging and color calibration techniques. The sensing platform offers higher accuracy for cross references, and is capable of simultaneous detection and discrimination of different metal ions in even real water samples. It demonstrates great potential for semiquantitative and even qualitative analysis with a sensitivity below the safe limit concentrations, and a controlled error range.
重金属在痕量水平下具有高度毒性，其污染对全球环境和公共健康构成了巨大威胁。目前的检测方法需要昂贵的仪器和繁琐的操作，只能在集中式实验室中进行。在此，我们报告了一种低成本的基于纸张的微流控分析装置（μPAD），用于简便、便携和一次性监测汞、铅、铬、镍、铜和铁离子。μPAD 上预先加载了包含离子或分子的三重指示剂或配体，加入金属离子后，比色指示剂会引起肉眼可见的颜色变化。颜色特征使用数字成像和颜色校准技术在红、绿、蓝或 RGB 空间的三维空间中进行定量分析。该传感平台提供了更高的准确性，可用于交叉参考，并能够在真实水样中同时检测和区分不同的金属离子。它具有在安全限量浓度以下进行半定量甚至定性分析的巨大潜力，并且具有可控的误差范围。
