Mathematics and Physics Department, School of Engineering, Australian College of Kuwait, Safat 13015, Kuwait.
Institute for Sustainable Industries and Livable Cities (ISILC), Victoria University, Melbourne, VIC 8001, Australia.
Int J Mol Sci. 2021 Jun 3;22(11):6053. doi: 10.3390/ijms22116053.
Lead detection for biological environments, aqueous resources, and medicinal compounds, rely mainly on either utilizing bulky lab equipment such as ICP-OES or ready-made sensors, which are based on colorimetry with some limitations including selectivity and low interference. Remote, rapid and efficient detection of heavy metals in aqueous solutions at ppm and sub-ppm levels have faced significant challenges that requires novel compounds with such ability. Here, a UiO-66(Zr) metal-organic framework (MOF) functionalized with SO3H group (SO3H-UiO-66(Zr)) is deposited on the end-face of an optical fiber to detect lead cations (Pb2+) in water at 25.2, 43.5 and 64.0 ppm levels. The SO3H-UiO-66(Zr) system provides a Fabry-Perot sensor by which the lead ions are detected rapidly (milliseconds) at 25.2 ppm aqueous solution reflecting in the wavelength shifts in interference spectrum. The proposed removal mechanism is based on the adsorption of [Pb(OH2)6]2+ in water on SO3H-UiO-66(Zr) due to a strong affinity between functionalized MOF and lead. This is the first work that advances a multi-purpose optical fiber-coated functional MOF as an on-site remote chemical sensor for rapid detection of lead cations at extremely low concentrations in an aqueous system.
用于生物环境、水基资源和药物化合物的铅检测主要依赖于使用大型实验室设备（如 ICP-OES）或基于比色法的预制传感器，但这些方法存在选择性和低干扰等局限性。在 ppm 和亚 ppm 水平下，远程、快速和高效地检测水溶液中的重金属一直面临着重大挑战，这需要具有这种能力的新型化合物。在这里，一种功能化了 -SO3H 基团的 UiO-66(Zr) 金属有机骨架 (MOF)（SO3H-UiO-66(Zr)）被沉积在光纤的端面上，以检测水中的铅阳离子 (Pb2+)，浓度分别为 25.2、43.5 和 64.0 ppm。SO3H-UiO-66(Zr) 系统提供了一个 Fabry-Perot 传感器，通过该传感器可以在 25.2 ppm 水溶液中快速（毫秒级）检测到铅离子，反映在干涉光谱中的波长移动。所提出的去除机制基于水中 [Pb(OH2)6]2+ 在 SO3H-UiO-66(Zr) 上的吸附，这是由于功能化 MOF 和铅之间的强亲和力。这是第一项将多用途光纤涂层功能 MOF 作为现场远程化学传感器用于在水溶液中极低速率下快速检测铅阳离子的工作。
