内蒙古锦鸡儿属植物叶片矿质元素的电感耦合等离子体质谱分析

基于内蒙古典型草原相同生境条件，以柠条锦鸡儿、小叶锦鸡儿和狭叶锦鸡儿为灌木类植物的代表，研究锦鸡儿属植物叶片中11种矿质元素含量特征及离子平衡对植物适应环境尤其是逆境的响应。应用在线内标加入和碰撞/反应池(ORS)技术消除质谱干扰，以电感耦合等离子体质谱法(ICP-MS)快速、同时测定植物叶片中K，Ca，Mg，P，Mn，B，Na，Zn，Cu，Ni和Mo等多种矿质元素含量。以硝酸和双氧水为消解酸，微波仪消解样品，选择相应同位素，以3.5 mL·min-1为He流速；K，Na，Ca，Mg和P元素检出限为0.62～2.90 μg·L-1；Cu，Zn，Mn，Ni，Mo和B元素检出限为0.01～0.12 μg·L-1；样品加标回收率在82.0%～117.2%，相对标准偏差在1.12%～3.68%之间，具有较高的准确度和精密度。该方法实现对灌木类植物样品中大量元素和微量元素进行同时、快速及批量分析，结果显示三种锦鸡儿属植物叶片矿质元素含量大小顺序均为K>Mg>P>Ca，K+作为抗旱性机制中重要的渗透调节物质，含量最高，均值达到1.27%；狭叶锦鸡儿叶片Mn，Cu和Zn元素含量高于柠条锦鸡儿和小叶锦鸡儿，后两者一致；叶片11种矿质离子平衡总量以柠条锦鸡儿最大(40 089.32 μg·g-1)，明显高于狭叶锦鸡儿和小叶锦鸡儿。该研究通过对锦鸡儿属植物叶片多种矿质元素进行快速、同时测定并分析逆境适应下多种矿质元素含量特征，初步探讨植物叶片矿质离子平衡对植物抗性的响应。

Study on the Determination of Mineral Elements in Three Caragana Fabr. Species in Inner Mongolia by Inductively Coupled Plasma Mass Spectrometry

Based on the same habitat conditions of typical steppe in Inner Mongolia, studies were carried out about the response of mineral elements of Caragana korshinskii, C. microphylla and C. stenophylla as the representative of shrub species to plant drought resistance. Samples of the grass leaves were digested with microwave digestion, and 11 mineral elements contents of K, Ca, Mg, P, Mn, B, Na, Zn, Cu, Ni and Mo in the solution were determined with Inductively Coupled Plasma Mass Spectrometry (ICP-MS) with the equipment of collision/reaction pool (ORS) which effectively eliminate interference. HNO₃ and H₂O₂ was used to achieve the complete decomposition of the complex matrix in a closed-vessel microwave oven. The results showed that the limit of detection for the K, Na, Ca, Mg and P varied from 0.62 to 2.90 μg·L-1, and the Cu, Zn, Mn, Ni, Mo and B from 0.01 to 0.12 μg·L-1. The recovery rate was found to be 82.0%~117.2% in adding standard recovery experiment and the relative standard deviation(RSD) was between 1.12% and 3.68%, which mean that this method was simple, sensitive and precise. The results showed that the contents of mineral elements in the leaves of three species were K>Mg>P>Ca, and it is possible that the determination of the contents of mineral elements in the plant species were made in the same time, promptitude and batch analysis. The concentration of Mn, Cu and Zn in C. microphylla were higher than that of C. korshinskii and C. stenophylla, and the latter were similar. Of the total amount of the 11 kinds of mineral ions of the three species, C. korshinskii was the highest (40 089.32 μg·g-1), which was significantly higher than that of C. microphylla and C. stenophylla. As the routine method in our laboratory, the satisfactory results indicate that it has great potential for the determination of all mineral elements by one single analysis and batch measurement in plant samples. This study provides basic data for the study of plant nutrition and ion groups.