Fast Quantification of Humic Substances and Organic Matter by Direct Analysis of Sediments Using DRIFT Spectroscopy

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• 作者：Luc Tremblay and Jean-Pierre Gagné
• 刊名：Analytical Chemistry
• 出版年：2002
• 出版时间：July 1, 2002
• 年：2002
• 卷：74
• 期：13
• 页码：2985 - 2993
• 全文大小：147K
• 年卷期：v.74,no.13(July 1, 2002)
• ISSN：1520-6882

文摘

A simple method based on diffuse reflectance coupledwith infrared Fourier transform spectroscopy (DRIFTS)has been developed for the quantification and the characterization of sedimentary (or soil, peat, etc.) humicsubstances. Under optimized conditions, the quantification of humic substances or total organic matter ispossible with DRIFTS at a frequency of 2930 cm^-1 usingwhole dry sediment samples. A study of the operationalparameters that affect the DRIFTS signal shows theimportance of normalizing analysis conditions, especiallythe diffuse reflectance accessory alignment, the particlesize and compaction, and the homogeneity of the powdered samples, to obtain reproducible quantitative analyses. The quantification of total humic substances byDRIFTS correlates well with the concentrations determined using classical extraction methods. DRIFTS analysis requires only a few minutes instead of tedious extractions of humic substances. Moreover, the distribution oftotal organic matter and of fulvic acids, humic acids, andhumin can also be obtained. Analysis of natural samplesindicates that a calibration using humic material representative of the studied area provides the most accuratequantification. The fast screening of organic matter fractions by DRIFTS on intact natural samples provides usefulquantitative and qualitative information that can be usedin environmental or monitoring studies.