Quantitative Analysis of Non-UV-Absorbing Cations in Soil Samples by High-Performance Capillary Electrophoresis. An Experiment for Undergraduate Instrumental Analysis Laboratory

Abstract

Cations such as Ca2+, Mg2+, K+, NH4 +, Na+, Mn2+, and Zn2+ are very important in soil even though some of them are present in low concentrations. Plants, to grow well, must be planted in soil with cations in sufficient quantities and proper ratios. The number of cations and the variability of their concentrations in soils may make soil too complex for quantitative analysis by traditional methods. We describe a high-performance capillary electrophoresis (HPCE) experiment for quantitative analysis of cations in soil samples. The method is economical and fast, and is potentially applicable to normal soil analysis. Since HPCE is a useful and modern technique, it is necessary that undergraduate students in chemistry learn to use it. This experiment is designed as a one- or two-week laboratory experiment in Instrumental Analysis. It has been performed in the laboratory at Truman State University for two years, and students have obtained excellent results.

Competitive Sorption between Oxalate and Phosphate in Soil: An Environmental Chemistry Laboratory Using Ion Chromatography

“…Soil chemistry, a key component of environmental chemistry, has been largely ignored in undergraduate chemistry curricula over the years. In recent years, several experiments on the analysis of organic and inorganic contaminants in soils, designed for environmental chemistry laboratory courses, have been published in this Journal (1)(2)(3)(4)(5)(6)(7)(8)(9). However, lab exercises that illustrate important chemical reactions in soils are lacking.…”

Recent advances and trends in capillary electrophoresis of inorganic ions

“…New procedures for determining common anions in drink- ing [180,181], rain [180], tap [47,55,98,115], mineral [47,55,98,115], river [55,98,142,180,182], groundwater [183], seawater [120,121,162,164,184], waste water [185], and soil extracts [186] or oxoanions in river water [187] were reported. Similar aquatic samples analyzed for alkali and alkaline earth metal ions encompass tap [188], rain [189], river [190], natural [191], underground water [192] and soil extracts [191,193], while transition metals were quantitatively characterized in mineral water [194], river water [133,190], and soil samples [193]. Different principles can be employed for simultaneous anion and cation determination by CE.…”

Capillary Electrophoresis with Laser-Induced Fluorescence Detection for the Diagnosis of Phenylketonuria: A Versatile Wet or Dry Laboratory Experiment in Upper-Level Undergraduate Analytical Chemistry

“…A number of undergraduate laboratory experiments utilizing CE have been developed subsequent to the availability of CE instrumentation analyzing various small molecules, − inorganic ions, − and biopolymers. ,− While effective in demonstrating the use of CE across a wide range of compounds, these experiments utilize UV absorbance almost exclusively as a means of detection while neglecting to utilize other detection methods. To our knowledge, an undergraduate laboratory experiment using CE-LIF has yet to be published.…”