Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
J Hazard Mater. 2024 Oct 5;478:135578. doi: 10.1016/j.jhazmat.2024.135578. Epub 2024 Aug 18.
Establishing a method similar to ICP-MS that can quantitatively analyze multiple heavy metals simultaneously, conveniently, and in situ is highly anticipated. In this study, we integrated the sensing elements of multiple targets and different fluorescence reporting elements to construct an engineered Escherichia coli. When these targets are present, the engineered bacteria can emit a fluorescent signal at the corresponding wavelength. To avoid the inability to accurately distinguish and quantify the content of each target due to the overlap of fluorescence signals when multiple targets coexist, a hydrogel-based separation platform similar to a separation column was constructed. The hydrogel platform can change the detection limit (LOD) and sensitivity by adjusting the adsorption strength towards different targets, so as to realize the differentiation and recognition of their respective detection signals. The LODs of this new detection method for Cd(II), Hg(II), As(III), and Pb(II) are 1.249, 0.380, 3.917, and 0.755 μg/L, respectively. In addition, this biosensor system was applied to detect coexisting Cd(II), Hg(II), As(III), and Pb(II) in actual samples with a recovery rate of 85.61-110.30 %, which is consistent with the classical ICP-MS detection results, confirming the accuracy and reliability of the method for detecting multiple heavy metal coexisting samples.
建立一种类似于 ICP-MS 的方法，可以同时、方便、原位定量分析多种重金属，这是非常令人期待的。在本研究中，我们整合了多个目标和不同荧光报告元素的传感元件，构建了一种工程大肠杆菌。当这些目标存在时，工程细菌可以在相应的波长处发出荧光信号。为了避免由于多个目标共存时荧光信号的重叠而无法准确区分和定量每个目标的含量，我们构建了一个类似于分离柱的基于水凝胶的分离平台。该水凝胶平台可以通过调整对不同目标的吸附强度来改变检测限（LOD）和灵敏度，从而实现各自检测信号的区分和识别。该新检测方法对 Cd(II)、Hg(II)、As(III)和 Pb(II)的检测限分别为 1.249、0.380、3.917 和 0.755μg/L。此外，该生物传感器系统还应用于实际样品中同时存在的 Cd(II)、Hg(II)、As(III)和 Pb(II)的检测，回收率为 85.61-110.30%，与经典的 ICP-MS 检测结果一致，证实了该方法检测多种重金属共存样品的准确性和可靠性。
