摘要
由于近红外光谱的独特优势,在实际复杂样品分析中发挥了重要作用.但由于近红外光谱的信号相对较弱,无机离子在近红外光谱中一般没有响应,因此难以用于微量成分特别是无机微量组分的测定.总结了近红外光谱技术在环境、土壤、植物及生物样品分析中的应用,说明了近红外光谱用于无机微量成分分析的原理.由于近红外光谱技术一般通过多元校正方法进行定性定量分析,利用组分间的相互作用或组分含量之间的相关性可以实现微量组分或无光谱响应组分的定量分析.还总结了富集技术在近红外光谱分析中的应用,利用富集技术可实现稀溶液中金属离子含量的快速测定,并可以改善分析的灵敏度和检测限.
Near infrared spectroscopy （NIRS） has been widely used in analyzing various real complex samples due to its superiority in fast and non-destructive determination. It is difficult, however, for the technique to analyze the components of micro-content, especially the inorganic components, because NIR spectrum contains only the weak signals of C—H, O—H and N—H, and inorganic components generally generate no response in the spectrum. In this review, the principle and applications of NIRS in analyzing inorganic components in environmental, soil, plant and bio-samples are summarized. The feasibility of applying NIRS in micro-inorganic analysis was proved by various applications of the technique in analyzing lake or river sediments, forest or farmland soils, straw, amaranth, clover, paprika, rice, wheat, meats, and sea foods. Because multivariate calibration technique is generally adopted in NIR spectral analysis, quantitative analysis can be achieved by modeling the spectral responses in which the interactions of the inorganic components and organic contents are included or by using the correlationship between the micro and macro components. However, the models must be used with care in such applications because they may fail when the predicted samples are heavily deviated from the calibration ones. Furthermore, applications of preconcentration techniques in NIR analysis are also summarized in this paper. By adsorption of an inorganic analyte onto the surface of a high efficient adsorbent from a dilute solution, the interactions between the analyte and the adsorbent can be directly measured by using NIR diffuse reflectance spectroscopy （NIRDRS）, and the relationship between the contents of the analyte and the spectra can be modeled with multivariate calibration techniques. The adsorbents of functionalized resins, thiol-functionalized magnesium phyllosilicate clay, nano-hydroxyapatite, etc. have been studied for detection of micro inorganic ions in dilute solutions such as Hg^2＋, Ag^＋, Pb^2＋, Zn^2＋, Cu^2＋, Co^2＋, Ni^2＋, Cd^2＋ and Cr^3＋. The results of these studies showed that the adsorption can significantly improve the detection limit and fast detection can be achieved by NIRDRS measurements and multivariate calibration.
出处
《化学学报》
SCIE
CAS
CSCD
北大核心
2012年第20期2109-2114,共6页
Acta Chimica Sinica
基金
项目受国家自然科学基金(No.20835002)资助~~
关键词
近红外光谱
微量分析
无机组分
富集
相关性
多元校正
near infrared spectroscopy
micro-analysis
inorganic component
preconcentration
correlation
multivariatecalibration
作者简介
邵学广,E-mail:xshao@nankai.edu.cn
