Xu Ronghui, Tan Lu, Tian Wenwen, Ma Kaili, Zheng Yi, Wang Ding, Zheng Yingping, Lou Yongbing
School of Chemistry and Chemical Engineering, Southeast University, Nanjing, 211189, P. R. China.
Department of Chemistry, Anhui University, Hefei, 230601, P. R. China.
Mikrochim Acta. 2025 Jun 23;192(7):442. doi: 10.1007/s00604-025-07225-7.
To address the urgent requirements for fast and on-site hexavalent chromium (Cr(VI)) detection, we developed a dual-mode sensing platform integrating surface-enhanced Raman spectroscopy (SERS) and colorimetry combined with smartphone-assisted visual detection using gold-core silver-shell nanoparticles (Au@Ag NPs). The SERS mode leveraged the plasmonic enhancement of Au@Ag NPs, achieving ultrahigh sensitivity with a detection limit of 0.074 nM and a linear range spanning five orders of magnitude. Simultaneously, the colorimetric mode utilized smartphone-assisted RGB (Red-Green-Blue) analysis to quantify Cr(VI)-induced nanoparticle etching, attaining a detection limit of 2.5 µM, surpassing conventional colorimetric sensors. The synergy of dual-mode detection enabled cross-validated quantification: SERS for trace-level determinations and smartphone-based colorimetry for rapid on-site screening. This platform demonstrated exceptional selectivity against interfering ions and robust performance in real-world applications, including rice and environmental water samples, with recoveries of 98.10-104.36%. By combining nanotechnology with portable devices, our work provides a cost-effective, user-friendly, and field-deployable solution for Cr(VI) monitoring in environmental safety and food quality control.
为满足快速现场检测六价铬（Cr(VI)）的迫切需求，我们开发了一种双模式传感平台，该平台集成了表面增强拉曼光谱（SERS）和比色法，并结合使用金核银壳纳米粒子（Au@Ag NPs）的智能手机辅助视觉检测。SERS模式利用Au@Ag NPs的等离子体增强作用，实现了超高灵敏度，检测限为0.074 nM，线性范围跨越五个数量级。同时，比色模式利用智能手机辅助的RGB（红-绿-蓝）分析来量化Cr(VI)诱导的纳米粒子蚀刻，检测限达到2.5 μM，超过了传统比色传感器。双模式检测的协同作用实现了交叉验证定量：SERS用于痕量水平测定，基于智能手机的比色法用于快速现场筛查。该平台对干扰离子表现出优异的选择性，在包括大米和环境水样在内的实际应用中具有稳健的性能，回收率为98.10-104.36%。通过将纳米技术与便携式设备相结合，我们的工作为环境安全和食品质量控制中的Cr(VI)监测提供了一种经济高效、用户友好且可现场部署的解决方案。
