ABSTRACT
A strategy for determining the bioaccessibility of bromine and iodine from edible seaweeds was proposed for the first time using microwave-induced combustion (MIC) and ion chromatography coupled to mass spectrometry (IC-MS) after in vitro digestion. The concentrations of bromine and iodine in edible seaweeds using the proposed methods (MIC and IC-MS) were not statistically different from those using MIC and inductively coupled plasma mass spectrometry (p > 0.05). Trueness was assessed by recovery experiments (101-110%, relative standard deviation <10%). Following an in vitro digestion protocol, MIC was proposed as sample preparation for bioaccessible and residual fractions. Using this strategy, the mass balance totaled from 97 to 111%. No statistical difference (p > 0.05) was observed between the total concentration of bromine or iodine and their concentration in bioaccessible and residual fractions for three edible seaweed species, indicating full analyte quantification in the fractions.
ABSTRACT
A versatile, rapid and safe green method for chlorine and sulfur determination using ion chromatography in cereals and legumes was developed. Microwave-induced combustion was evaluated for sample preparation. Ultrapure water and alkaline solutions were assessed for absorption of the analytes. Water was selected because good recoveries (97-109%) were obtained for both analytes. Low consumption of reagents and small quantities of waste are two important advantages of the proposed method. Accuracy was evaluated by analysis of a standard reference material, which agreed with certified values (91-101%). The results for repeatability (RSDsâ¯≤â¯4%) and intermediate precision (RSDsâ¯≤â¯7%) prove the good precision of the proposed method. Limits of quantification were 16 and 17â¯mgâ¯kg-1 for Cl and S, respectively. Concentrations of Cl and S varied across a wide range (Cl: 35-930â¯mgâ¯kg-1; S: 678-5124â¯mgâ¯kg-1) for 34 samples analyzed, which were, for most of the results, close to the values found in the literature.