Ligand-exchange indirect conductometric detection of electrically neutral carbohydrates and alcohols after high-performance liquid chromatographic separation

Abstract

Indirect conductometric detection of electrically neutral sugars and alcohols Is described. These compounds are not directly measured with conductometry, but some of them were detectable wHh a boric acid eluent as previously reported. However, most of polysaccharides and alcohols were not detectable because they form only the un-lonlzed borate complexes. Use of a polyol-borate eluent made It posslblé

Model for conductometric detection of carbohydrates and alcohols as complexes with boric acid and borate ion in high-performance liquid chromatography

“…1982, 54, 986-990. Sir: In recent articles (1)(2)(3)(4)(5), Okada has demonstrated the utility of indirect conductometric detection of electrically neutral sugars and alcohols through their complexes in boric acid solution. The use of a boric acid eluent provides a highly sensitive means of detection for monosaccharides, lactose, and sugar alcohols but not for polysaccharides (other than lactose) and simple alcohols.…”

Indirect conductometric detection of poly(oxyethylenes) after chromatographic separation

“…Nonionic carbohydrates forming the ionic borate complexes (or enhancing the dissociation of boric acid by forming complexes) gave positive conductometric responses (8). Those forming neutral borate complexes (or not enhancing acidity of boric acid) were indirectly detected by use of an ionic carbohydrate-borate complex as a mobile phase additive (9). Compounds containing poly(oxyethylenes) (POEs) as a part of the structure form metal complexes with some types of alkali, alkaline-earth, and transition metals (10).…”