Considerations in the Determination of Boron at Low Concentrations

by R. Gregory Downing, Philip Strong, B. Michael Hovanec, and Jack Northington

published in Biological Trace Element Research, 66, 3-21 (1998)

Abstract

Experimental evidence now supports the nutritional essentiality of boron (B) in some biological systems, and accordingly, the need for reliable analytical B data is increasing. However, the accurate determination of B in biological materials is a formidable challenge at low concentrations (<1 mg B/kg). Recent studies still show significant analytical discrepancies in the analysis of animal tissues and fluids, despite the development of instrumental techniques such as TIMS, ICP-MS, ICP-ES, ICAP, SIMS, NA-MS, PGAA, NRA, and so forth, which have demonstrated detection limits approaching or exceeding ug B/kg concentrations. Since boric acid is both volatile and ubiquitous in nature, the chemical and physical pathways for B contamination and its loss are

 manifold, especially during sample preparation. An added obstacle is the inadequacy of biological reference materials certified for B below mg B/kg. With an emphasis toward sample preparation and ICP-MS analysis, examples are provided in this article to help the analyst avoid common problems associated with the analysis of B from biological sources. Topics that are discussed include contamination from Teflon vessels during microwave digestion, losses owing to freeze-drying, B isotopic variations, standards preparation, reagent backgrounds, and instrumental interferences.

For additional information see:

• Boron Skin Absorption

• Boron and Iodine by ICPMS

For a quotation...

Formerly West Coast Analytical Service (WCAS) and Bodycote Testing Group