Determination of myo‐inositol phosphates in food samples by flow injection‐capillary zone electrophoresis

Abstract

A capillary electrophoresis (CE) method with indirect photometric detection was developed to identify and quantify myo-inositol phosphates in food samples. A flow-injection (FI) system including a micro-column containing anionic exchange resin was used for the solid-phase extraction of the myo-inositol phosphates with a view to their preconcentration. The FI system was automatically coupled to CE equipment via a mechanical interface. The overall analysis time was shortened by incorporating an FI system for myo-inositol hexakisphosphate monitoring. The limit of detection for myo-inositol phosphates as determined by FI-CE ranged from 11 to 26 micromol/L and the coefficient of variation from 3.9 to 5.0%. On the other hand, the limit of detection and coefficient of variation for myo-inositol hexakisphosphate as monitored by the FI system were 75 micromol/L and 2.9%, respectively. The proposed method was successfully applied to a variety of food samples with recoveries ranging from 96.0 to 107.7% and the precision from 3.9 to 7.9%. Based on the results, the content of myo-inositol hexakisphosphate in nuts was two or three times higher than that in legumes.

Recent advances in the application of capillary electromigration methods for food analysis

“…Apart of the applications described above, CE methods have also been used to analyze other different compounds in foods [163][164][165][166][167][168][169][170][171][172][173][174]. Thus, capillary electromigration methods have successfully been applied for the simultaneous determination of multiple constituents in real beer samples [163,164].…”

“…A CE method with indirect photometric detection was developed to identify and quantify myoinositol phosphates in foods [167]. These compounds seem to have some benefits to human health including preventive, therapeutic action as anticancer agents, antioxidants and inhibitors of the crystallization of pathological calcium salts such as renal calculi and tissue calcifications.…”

“…The flow injection system was automatically coupled to the CE instrument via a mechanical interface. The proposed method was applied to a variety of food samples observing that the content of myo-inositol hexakisphosphate in nuts was almost three times higher than in legumes [167].…”

Recent advances in capillary electrophoresis and capillary electrochromatography of pollutants

“…Many different online preconcentration techniques have been developed to improve the LOD for CE [86][87][88]. In general, these techniques are designed to compress analyte bands within the capillary, thereby increasing the volume of sample that can be injected without loss of CE efficiency.…”

Analytical approaches to expanding the use of capillary electrophoresis in routine food analysis

“…Mini-filters were used for filtering and introducing the wine samples into the manifold, and the analytes (methylamine, putrescine, histamine, cadaverine, ethanolamine, propylamine, isopropylamine, isoamylamine, tyramine, and phenethylamine) were preconcentrated prior to their introduction as a treated sample plug in the CE equipment. A similar arrangement was used for the determination of myo-inositol phosphates in food samples (lentils, almonds, nuts, and hazelnuts) [57].…”