Determination of anionic trace impurities in glycerol by capillary isotachophoresis with enlarged sample load

Recent progress in capillary isotachophoresis

“…Ammonium, sodium, potassium, magnesium, and calcium cations were determined in rain water by this technique [107]; complete resolution of all cations was reached at LODs in the range of 0.4 to 2.1´10 ±6 M using conductivity detection. Anionic trace impurities in glycerol (nitrate, sulfate, chlorate, nitrite, oxalate, fluoride, formate and phosphate) were determined up to an analyte-to-bulk ratio of 1:41 0 7 (preseparation LE: 10 mM HCl adjusted to pH 3.2 with b-alanine; analytical capillary LE: 5 mM HCl, BTP, adjusted to pH 3.6 with b-alanine; TE: citric acid) [108]. A similar approach was used to determine trace anionic impurities in acetic acid (nitrate, sulfate, nitrite, fluoride, formate, phosphate and oxalate) up to an analyte-toexcess ratio of 1:3´10 5 [109].…”

Application of isotachophoresis in food analysis

“…Even 30% w/w water solution of sucrose could have been injected into the analyzer and detection limits at ppm levels were thus achieved. Similarly, Meissner et al [29] used CITP (column-coupling instrument) for the determination of ionic impurities in glycerol and due to a large sample load they have reached an LOD of 10 ±5 % w/w.…”

Graphic data analysis and complex formation curves as modeling and optimization tools for characterization of Cu–(buffer)x–(OH)y systems involving BTP or BES in aqueous solution

“…It has two secondary amines, which are responsible for its two protonation constants, as shown in figure 1. The buffering pH range of BTP (6.30 < pH < 9.50) is of interest in plant physiology [4], chromatography [5,6], and biotechnology [7]. The structure of BTP suggests that it should be a strong complexing agent.…”