Sensitivity and Calibration of the FT-IR Spectroscopy on Concentration of Heavy Metal Ions in River and Borehole Water Sources
Sensitivity and Calibration of the FT-IR Spectroscopy on Concentration of Heavy Metal Ions in River and Borehole Water Sources
复制标题
河流和钻孔水源中重金属离子浓度的傅立叶变换红外光谱的灵敏度和校准
作者：
Matthew Mamera;J. V. van Tol;M. P. Aghoghovwia;E. Kotzé
水源中的重金属会威胁人类的生命和环境。分析时间、化学试剂需求和每次分析的样品量有助于监测污染物。傅里叶变换红外光谱法（FT-IR）由于其成本效益和准确性，在重金属元素的调查中得到了显着的发展。使用化学计量学模型如偏最小二乘法（PLS）和主成分回归分析（PCA）将来自许多校准样品的多个光谱强度与识别的分析物相关联。研究了FT-IR光谱法测定水源水中重金属（Ag、Cd、Cu、Pb和Zn）的方法。将FT-IR测量结果与原子吸收光谱仪（AAS）测量结果进行了比较。采用主成分分析和偏最小二乘法定量分析方法进行了FT-IR校正。光谱分析进行了使用衰减全反射（ATR-FTIR）技术在QwaQwa，南非（SA）在两个季节内采样的三条河流和四个钻孔水源。PLS模型具有良好的R2值，范围为0.95至1，PCA模型的范围为0.98至0.99。在0.001和0.05水平上，PLS和PCA模型对水样中Cd和Pb的检测结果存在显著差异。主成分分析模型检测到更多的Ag浓度（在选定的地点为100 mg L−1）。PLS和PCA模型仅对Zn离子的检测率较低，大多数高于45 mg L−1，偏离AAS测量值（<0.020 mg L−1）。FT-IR光谱显示出良好的潜力，用于重金属测定的目的。
Heavy metals in water sources can threaten human life and the environment. The analysis time, need for chemical reagents, and sample amount per analysis assist in monitoring contaminants. Application of the Fourier Transform Infrared (FT-IR) Spectroscopy for the investigation of heavy metal elements has significantly developed due to its cost effectiveness and accuracy. Use of chemometric models such as Partial Least Square (PLS) and Principle Component Regression Analysis (PCA) relate the multiple spectral intensities from numerous calibration samples to the recognized analytes. This study focused on the FT-IR calibration and quantification of heavy metals (Ag, Cd, Cu, Pb and Zn) in surveyed water sources. FT-IR measurements were compared with the atomic absorption spectrometer (AAS) measurements. Quantitative analysis methods, PCA and PLS, were used in the FT-IR calibration. The spectral analyses were done using the Attenuated Total Reflectance (ATR-FTIR) technique on three river and four borehole water sources sampled within two seasons in QwaQwa, South Africa (SA). The PLS models had good R2 values ranging from 0.95 to 1 and the PCA models ranged from 0.98 to 0.99. Significant differences were seen at 0.001 and 0.05 levels between the PLS and PCA models for detecting Cd and Pb in the water samples. The PCA models detected Ag concentrations more (˂0 mg L−1 on selected sites). Both the PLS and PCA models had lower detection only for Zn ions mostly above 45 mg L−1 deviating from the AAS measurements (<0.020 mg L−1). The FT-IR spectroscopy demonstrated good potential for heavy metal determination purposes.