梵净山白茶无机元素含量测定分析

Fanjing Mountains White Tea Content of Inorganic Elements Analysis

利用电感耦合等离子体质谱仪(ICP-MS)测定梵净山白茶中无机元素。结果表明:梵净山白茶中宏量元素含量大小依次为Na<Mg<Ca<K,其中K的含量最高达18 142.604 mg/kg,微量元素的含量大小依次为Mo<Se<Co<Cr<Cu<Zn<Fe,分别为0.052 9,0.111 1,0.291 5,0.967 8,14.607 2,38.985 9和249.316 5 mg/kg,在0~1 000 ng/m L内呈良好的线性关系(r≥0.999 9),方法检出限为0.000 2~5.908 1 mg/kg,相对标准偏差(RSD)为0.31%~4.37%(n=6),加标回收率为92.53%~102.56%,对茶叶标准物质(GBW 07605)进行测定,结果令人满意。该方法动态线性范围宽、分析速度快、灵敏度高、精密度高、准确度高,各项分析性能指标均达到要求,适用于食品中无机元素的测定。

Using inductively coupled plasma mass spectrometry （ICP-MS） of inorganic elements in the Fanjing Mountain white tea was determined. The results showed that the Fanjing mountains of macro elements content in white tea size followed by Na〈Mg〈Ca〈K, among them, the content of K was up to 18 142.604 mg/kg, the content of trace element size of Mo〈Se〈 Co〈Cr〈Cu〈Zn〈Fe, were 0.052 9, 0.111 1, 0.291 5, 0.967 8, 14.607 2, 38.985 9 and 249.316 5 mg/kg, within 0-1 000 ng/ mL had good linear relationship （r 0.999 9 or higher）, method detection limit was 0.000 2-5.908 1 mg/kg, relative standard deviation （RSD） was 0.31%-4.37% （n=6）, the recovery rate was 92.53%-102.56%, standard substance in tea （GBW 07605） was determined, the result was satisfactory. The method of dynamic linear range was wide, fast analysis speed, high sensitivity, high precision, high accuracy, the analysis of performance indicators was up to par, which was suitable for the determination of inorganic elements in food.