Synthesis and application of a boronic acid-substituted silica for high-performance liquid affinity chromatography

Determination of urinary nucleosides by direct injection and coupled-column high-performance liquid chromatography

“…These clean-up procedures for urinary nucleosides need manual operation, resulting in artificial error and time consuming. Hagemeier et al [30,31] successfully prepared a boronic acid-substituted silica material, which was used for on-line sample processing and analyzed the purine nucleic acid components, but Pseu, a important RNA excretory product, is not quantitatively recovered at that operational condition. Here, the employed coupled-column HPLC system is illustrated in Fig.…”

“…It has binding capacity of 0.18 mmol nucleoside per gram dry weight and tolerates pH values from 2 to 12 as well as the usual organic solvents. The more details of its preparation and physicochemical properties have been described by Hagemeier et al [30]. The column 2 (250 mm × 4.6 mm I.D.)…”

“…Recently, Weimann et al [27] adopted the mode of the low-temperature reversed-phase liquid chromatography, which performed at 1 • C on a single ODS column for separation of six types of 8-hydroxylated guanine modifications in urine without any sample pre-treatment. Actually, coupled-column HPLC is a very adaptable strategy for the direct analysis of target compounds in biological fluids, as indicated by studies [28,29], including also the analysis of purine nucleic acid components [30,31]. In this study, we described a fully automated method for the determination of 14 urinary nucleosides by coupled-column liquid chromatography with UV detection.…”

Development of a Chromatographic Method for the Quantitative Determination of Minor Ribonucleosides in Physiological Fluids. Characterization and quantitative determination of minor ribonucleosides in physiological fluids, Part I

“…For synthesis of boronic acid-functionalized silica LiChrosorb Si 100, 5 μπι, (Merck) was substituted with γ-chloropropyltrimethoxysilane (generous gift from Dynamit Nobel, Troisdorf) and subsequently reacted with m^aminobenzene'boronic acid according to 1. c. (24). Meanwhile a boronic acid substituted silica of comparable quality is commercially available from Serva Feinbiochemica, Heidelberg s "Dihydroxyboryl-Polyol Si 100", 5 μπι.…”

“…As the material described was not suitable for this purpose we developed a new boronate silica which fulfilled the conditions required (24). By coupling the HPLAC System, developed in our laboratory, to reversed-phase HPLC (RP-HPLC) by a column switching technique, we finally evolved a Chromatographie System for the on-line clean-up and analysis of ribonucleosides in physiological fluids (25,26).…”