Determination of Boron in Plants and Plant-Derived Foods by Ultrasonic Nebulization-Inductively Coupled Plasma Atomic Emission Spectrometry with Addition of Mannitol

Abstract

Abstract An ultrasonic nebulization-inductively coupled plasma (ICP) atomic emission spectrometry procedure was developed to determine boron in plants and plant-derived foods. Samples were ashed at 550°C for 4 h, and the resulting ash was dissolved into a mannitol-nitric acid solution to form a boron- mannitol complex. Solutions were directly nebulized into ICP by an ultrasonic nebulizer. The memory effect—the main drawback for determining boron with the ultrasonic nebulizer—was minimized with addition of mannitol. Two National Institute of Standards and Technology (NIST) standard reference materials (SRM 1515 apple leaves and SRM 1547 peach leaves) and 25 food and plant materials spiked with NIST SRM 1515 were analyzed to verify method accuracy. Boron contents found in NIST standard samples were in excellent agreement with certified values. A detection limit (2σ) of 0.5 μg/L and typical recoveries of 93 to 106% from spiked selected samples were obtained.