ABSTRACT

Contamination by hexavalent chromium [Cr (VI)] poses a threat to groundwater quality and its detection at point source is essential to provide early mitigating solutions. In this work, we report the fabrication of paper-based sensing system embedded with a novel nano-chromogenic complex having spherical gold nanoparticles modified with 1,5-diphenylcarbazide dye. This Au-DPC Functionalized paper strip develops pink color in <2 sec upon interaction with Cr (VI). With the developed optical fiber device a limit of detection of 0.02 ppm was achieved within a linear range of 0.01–0.4 ppm. RGB color analysis and data driven predictive modelling (KNN-model) demonstrated highest balanced accuracy score of 0.833 and cross validation accuracy of 0.714. Further, the portable optical fiber-based device offers advantages such as real-time monitoring, remote sensing capabilities, and the ability to integrate with existing optical systems for enhanced detection and analysis.

摘要

六价铬 [Cr (VI)] 污染对地下水质量构成威胁，点源检测对于提供早期缓解解决方案至关重要。在这项工作中，我们报告了嵌入新型纳米显色复合物的纸基传感系统的制造，该复合物具有用 1,5-二苯卡巴肼染料修饰的球形金纳米颗粒。此A u- D PC F功能化纸条在与 Cr (VI) 相互作用后不到 2 秒内呈现粉红色。利用所开发的光纤装置，在 0.01–0.4 ppm 的线性范围内实现了 0.02 ppm 的检测限。RGB 颜色分析和数据驱动的预测模型（KNN 模型）显示出最高的平衡准确度得分为 0.833，交叉验证准确度为 0.714。此外，基于便携式光纤的设备还具有实时监控、遥感功能以及与现有光学系统集成以增强检测和分析的能力等优点。