Yang X Y, Hao Z Q, Li C M, Li J M, Yi R X, Shen M, Li K H, Guo L B, Li X Y, Lu Y F, Zeng X Y
Opt Express. 2016 Jun 13;24(12):13410-7. doi: 10.1364/OE.24.013410.
In this study, chemical replacement combined with surface-enhanced laser-induced breakdown spectroscopy (CR-SENLIBS) was for the first time applied to improve the detection sensitivities of trace heavy metal elements in aqueous solutions. Utilizing chemical replacement effect, heavy metal ions in aqueous solution were enriched on the magnesium alloy surface as a solid replacement layer through reacting with the high chemical activity metallic magnesium (Mg) within 1 minute. Unitary and mixed solutions with Cu, Pb, Cd, and Cr elements were prepared to construct calibration curves, respectively. The CR-SENLIBS showed a much better detection sensitivity and accuracy for both unitary and mixed solutions. The coefficients of determination R of the calibration curves were above 0.96, and the LoDs were of the same order of magnitude, i.e., in the range of 0.016-0.386 μg/mL for the unitary solution, and in the range of 0.025-0.420 μg/mL for the mixed solution. These results show that CR-SENLIBS is a feasible method for improving the detection sensitivity of trace element in liquid sample, which definitely provides a way for wider application of LIBS in water quality monitoring.
在本研究中，首次应用化学置换结合表面增强激光诱导击穿光谱法（CR-SENLIBS）来提高水溶液中痕量重金属元素的检测灵敏度。利用化学置换效应，水溶液中的重金属离子通过在1分钟内与高化学活性的金属镁（Mg）反应，以固体置换层的形式富集在镁合金表面。分别制备了含有Cu、Pb、Cd和Cr元素的单一溶液和混合溶液来构建校准曲线。CR-SENLIBS对单一溶液和混合溶液均显示出更好的检测灵敏度和准确性。校准曲线的决定系数R均高于0.96，检测限处于同一数量级，即单一溶液的检测限在0.016 - 0.386μg/mL范围内，混合溶液的检测限在0.025 - 0.420μg/mL范围内。这些结果表明，CR-SENLIBS是提高液体样品中痕量元素检测灵敏度的一种可行方法，这无疑为LIBS在水质监测中的更广泛应用提供了一条途径。
