Determination of Choline in Infant Formula by Ion Chromatography

Abstract

Choline was determined in infant formula by ion chromatography with suppressed conductivity detection. Samples were digested with 1M hydrochloric acid, filtered, diluted, and injected into the chromatographic system. Choline and the alkali and alkaline earth metals were separated on a high-resolution cation-exchange column and detected by suppressed conductivity. The method was linear between 2 and 200 mg/L (r2 = 0.9999), the concentration range of the diluted samples. This method accurately determined choline in powdered, concentrated, and ready-to-feed infant formulas. Recoveries of choline spikes into powdered infant formula at approximately 1, 0.8, 0.5, and 0.2 times the labeled value ranged from 85 to 114%. This method had good agreement for 8 blind duplicates. The values determined for these samples, which were used in an AOAC collaborative study of an enzymatic method, were consistent with the values determined by the enzymatic method.

Enhanced Electrocatalytic Detection of Choline Based on CNTs and Metal Oxide Nanomaterials

“…Several analytical assays are used for the determination of choline. These include GC-MS [31][32][33], thin-layer chromatography (TLC) [28], ion chromatography [34], liquid chromatography with electrospray ionization-isotope dilution mass spectrometry (LC-ESI-IDMS) [3], high-performance liquid chromatography-fluorescence detection (HPLC-FLD) [24], high-throughput methods based on normal-phase chromatography-tandem mass spectrometry (LC-MS/MS) [20], liquid chromatography with an electrochemical detector (LC-ED) [2], paired-ion HPLC [31], proton nuclear magnetic resonance (1H NMR) [18], capillary zone electrophoresis with an indirect UV detector (CE-UV) [35], enzyme-based chemiluminescence [36,37] and flow injection analysis [1,17]. These methods have been found to be reliable and applicable for choline sensing in real samples.…”

A rapid ion chromatography column-switching method for online sample pretreatment and determination ofl-carnitine, choline and mineral ions in milk and powdered infant formula

“…The conventional HPLC with different detectors, such as evaporative light scattering and mass spectrometry detection, 13 electrochemical detection and, 14 suppression conductivity detection 15 has restrictions in terms of weak chromophore, derivatization and redissolution of the extract in organic solvent. Also, IC with conductivity detection has been evaluated for the separation and determination of choline, 16 L-carnitine 17 sodium, potassium, magnesium and calcium ions 18,19 in food samples 20,21 and is an attractive alternative. It is well known that IC is a powerful analytical technique for the separation of cations, anions and polar and hydrophilic compounds.…”

Determination of betaine, l‐carnitine, and choline in human urine using a self‐packed column and column‐switching ion chromatography with nonsuppressed conductivity detection

“…Various methods have been reported for the determination of betaine, l‐ carnitine, and choline either alone or in various combinations in complex matrix. Previous reported methods such as GC , conventional HPLC , and IC were proposed for the determination of these target compounds either separately or simultaneously. The limitation of GC analysis is the need of conversion of betaine, l‐ carnitine, and choline into volatile derivatives .…”

“…In comparison, IC is a powerful analytical technique for the separation of cations, anions, and polar and hydrophilic compounds, such as sugars, amino acids, peptides, and proteins. Accordingly, IC with conductivity detection has been evaluated for the separation and determination . Here, we describe an IC method for simultaneous and rapid determination of betaine, carnitine, and choline in the human urine.…”