Department I. Analytical Chemistry, Reference Materials, BAM Federal Institute for Materials Research and Testing, Unter den Eichen 87, 12205 Berlin, Germany.
Anal Chem. 2011 Apr 1;83(7):2562-8. doi: 10.1021/ac102836h. Epub 2011 Mar 14.
We present a comprehensive chemical and mass spectrometric method to determine boron isotopic compositions of plant tissue. The method including dry ashing, a three-step ion chromatographic boron-matrix separation, and (11)B/(10)B isotope ratio determinations using the Cs(2)BO(2)(+) graphite technique has been validated using certified reference and quality control materials. The developed method is capable to determine δ(11)B values in plant tissue down to boron concentrations of 1 mg/kg with an expanded uncertainty of ≤1.7‰ (k = 2). The determined δ(11)B values reveal an enormous isotopic range of boron in plant tissues covering three-quarters of the natural terrestrial occurring variation in the boron isotopic composition. As the local environment and anthropogenic activity mainly control the boron intake of plants, the boron isotopic composition of plants can be used for food provenance studies.
我们提出了一种全面的化学和质谱方法来测定植物组织的硼同位素组成。该方法包括干法灰化、三步离子色谱硼基质分离以及使用 Cs(2)BO(2)(+)石墨技术测定 (11)B/(10)B 同位素比，已使用认证参考材料和质量控制材料进行了验证。该方法能够测定植物组织中硼浓度低至 1mg/kg 的 δ(11)B 值，扩展不确定度≤1.7‰（k = 2）。测定的 δ(11)B 值揭示了植物组织中硼的同位素组成存在巨大的同位素范围，涵盖了天然陆地硼同位素组成变化的四分之三。由于当地环境和人为活动主要控制着植物对硼的摄入，因此植物的硼同位素组成可用于食品来源研究。
