State Key Laboratory of Transient Optics and Photonics, Xi'an Institute of Optics and Precision Mechanics, Chinese Academy of Science, Xi'an, 710119, China.
Institute of Photonics & Photon-Technology, Northwest University, Xi'an 710069, People's Republic of China.
Analyst. 2022 Jun 27;147(13):3025-3034. doi: 10.1039/d1an02263f.
An accurate as well as highly sensitive label-free chemical sensing platform for the detection of various metal ions was demonstrated. The chemical sensor was derived from the micro-tapered long-period fiber grating (MLPG) by depositing graphene oxide (GO) by chemical-bonding and optical-tweezer effects. The enhancement in refractive index (RI) sensitivity as well as reusability was obtained by evaluating the deposition thickness in the range of approximately 97.7 to 158.9 nm. Based on the analysis of adsorption principles, the enhanced RI sensitivity leads to a limit of detection as low as 3.2 ppb. The highest sensitivities for the cases studied using sodium and manganese ions in a wide concentration range of 1 ppb to 1 × 10 ppb are respectively 2.2 × 10 dB per ppb and 3.2 × 10 dB per ppb. Mixture samples were also studied to evaluate the properties of sensing the doped ions. This demonstration of GO modified MLPG is bound to find potential applications that require sensing of mixed samples and illustrates significant importance in developing cost-effective, label-free, reusable, and real-time chemical sensors.
本文展示了一种用于检测各种金属离子的精确且高灵敏度的无标记化学传感平台。该化学传感器由微锥形长周期光纤光栅（MLPG）通过化学键合和光镊效应沉积氧化石墨烯（GO）衍生而来。通过评估沉积厚度约为 97.7 至 158.9nm 的范围，获得了折射率（RI）灵敏度和可重复使用性的增强。基于吸附原理的分析，增强的 RI 灵敏度导致检测限低至 3.2ppb。对于使用钠离子和锰离子在 1ppb 至 1×10ppb 宽浓度范围内进行研究的情况，灵敏度最高分别为 2.2×10dB/ppb 和 3.2×10dB/ppb。还研究了混合样品以评估掺杂离子的传感性能。GO 修饰的 MLPG 的这种演示必将找到需要混合样品传感的潜在应用，并在开发具有成本效益、无标记、可重复使用和实时化学传感器方面具有重要意义。
