Determination of borates in caviare by ion-exclusion chromatography.
A specific and rapid analytical procedure for the determination of borates in caviare was developed using ion-exclusion chromatography. Products require minimal pre-treatment, are simply extracted with eluent and filtered prior to chromatography. Isolation of the analyte as a 2:1 sorbitol-borate complex was accomplished using an anion exchange column with an eluent consisting of 2 mM heptafluorobutyric acid + 50 mM sorbitol with conductivity detection [corrected]. Among five sugar alcohols examined for complexation, sorbitol was found to provide optimum resolution and a 3-4 times enhancement of response over borate anion alone. The response of the complex was linear over at least a 100 fold range in concentration (0.1-10 micrograms boron/ml) with a correlation coefficient of 0.9997. Using a boric acid standard solution, the limits of detection and quantitation were 0.065 microgram/ml and 0.216 microgram/ml, respectively, calculated as boron. Replicate analyses (n = 5) for samples having commercially added borate (equivalent to 300-1000 micrograms/g boron) gave RSD values of 1.18-2.03%. Recoveries of borate from fortified samples having commercially added borate present varied from 94.5 to 101.1% while untreated samples exhibited recoveries of 78.5-108.0% over a concentration range of 23-1039 micrograms/g, calculated as boron.
Carlson
M
M
US Food and Drug Administration, MN 55401, USA.
Thompson
R D
RD
D000818:Animals; D001881:Borates / Q000032:analysis*; D002852:Chromatography, Ion Exchange / Q000379:methods; D005399:Fishes / Q000378:metabolism*; D005506:Food Contamination; D005520:Food Preservatives / Q000032:analysis*; D017747:Seafood / Q000032:analysis*; D013012:Sorbitol
D001881:Borates; D005520:Food Preservatives; D013012:Sorbitol