Abstract:
Fluorine, depending on its concentration and chemical form, is essential or toxic to humans and animals. Therefore, it is crucial to be able to determine it reliably. In this study, fluorine was determined in animal feed after extraction with HCl (gastric juice simulation). The standard potentiometric method with a fluoride-selective electrode (ISE) and newly developed high-resolution continuum source graphite furnace molecular absorption spectrometry (HR-CS GFMAS) method was applied. Feed samples turned out to be a challenge for HR-CS GFMAS. Chemical interferences (formation of competing molecules, CaF, GaCl, and GaP, instead of the target GaF molecule) and spectral effects (including a phosphorous molecule spectrum and atomic lines) were identified. An additional difficulty was caused by reagent contamination with F and memory effects. Difficulties were eliminated/reduced. The quality of ISE analysis was multi-directionally verified (including comprehensive proficiency testing). A risk of inaccuracy at low F concentration, where the calibration relationship is nonlinear, was investigated. The results of both methods were consistent, which confirms the accuracy of the methods and informs that the extracted fluorine is in fluoride form. The results of extensive ISE tests conducted in Poland in 2021-2023 have shown that, in most cases, the fluoride content is significantly lower than the threshold values.
摘要:
氟,取决于它的浓度和化学形式,对人类和动物是必需的或有毒的。因此,能够可靠地确定它是至关重要的。在这项研究中,用HCl(胃液模拟)提取后测定动物饲料中的氟。采用了氟化物选择电极(ISE)的标准电位法和新开发的高分辨率连续源石墨炉分子吸收光谱法(HR-CSGFMAS)。饲料样品被证明是HR-CSGFMAS的挑战。化学干扰(竞争分子的形成,CaF,GaCl,和GaP,而不是目标GaF分子)和光谱效应(包括磷分子光谱和原子线)被鉴定。试剂污染F和记忆效应引起了额外的困难。困难被消除/减少。对ISE分析的质量进行了多方向验证(包括全面的能力测试)。在低F浓度下存在不准确的风险,其中校准关系是非线性的,被调查。两种方法的结果一致,这证实了方法的准确性,并告知提取的氟是氟化物形式。2021-2023年在波兰进行的广泛的ISE测试结果表明,在大多数情况下,氟含量明显低于阈值。