Ferreira Edilene C, Anzano Jesús M, Milori Débora M B P, Ferreira Ednaldo J, Lasheras Roberto J, Bonilla Beatriz, Montull-Ibor Beatriz, Casas Justiniano, Martin Neto Ladislau
Embrapa Agricultural Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970, São Carlos, SP, Brasil.
Appl Spectrosc. 2009 Sep;63(9):1081-8. doi: 10.1366/000370209789379394.
Laser-induced breakdown spectroscopy (LIBS) is an emerging analytical technique to perform elemental analysis in natural samples independent of their physical state (solid, liquid, or gaseous). Due to its instrumental features, LIBS shows promising potential to perform analysis in situ and in environments at risk. Since the analytical performance of LIBS strongly depends on the choice of experimental conditions, each particular application needs a specific instrumental adjustment. The present study evaluated three LIBS instrumental parameters regarding their influences on signal-to-noise ratio (SNR) of seven elements in soil samples: laser pulse energy, delay time, and integration time gate. A multivariate technique was used due to the significant interaction among the evaluated parameters. Subsequently, to optimize LIBS parameters for each individual element response, a method for multiple response optimization was used. With only one simple screening design, it was possible to obtain a good combination among the studied parameters in order to simultaneously increase the SNR for all analytes. Moreover, the analysis of individual response for elements is helpful to understand their physical behavior in the plasma and also how they are embedded in the sample matrix.
激光诱导击穿光谱法（LIBS）是一种新兴的分析技术，可对天然样品进行元素分析，而无需考虑其物理状态（固体、液体或气体）。由于其仪器特性，LIBS在原位和危险环境中进行分析具有广阔的潜力。由于LIBS的分析性能在很大程度上取决于实验条件的选择，因此每个特定应用都需要进行特定的仪器调整。本研究评估了三个LIBS仪器参数对土壤样品中七种元素信噪比（SNR）的影响：激光脉冲能量、延迟时间和积分时间门。由于评估参数之间存在显著相互作用，因此使用了多元技术。随后，为了针对每个元素的响应优化LIBS参数，采用了一种多响应优化方法。仅通过一个简单的筛选设计，就有可能在所研究的参数之间获得良好的组合，以便同时提高所有分析物的信噪比。此外，对元素个体响应的分析有助于了解它们在等离子体中的物理行为，以及它们在样品基质中的嵌入方式。
