微波消解-断续流动-双道原子荧光光谱法测定南阳彩色小麦中的硒

Determination of Selenium in Nanyang Colored Wheat by Intermittent Flow-Double Channel-Atomic Fluorescence Spectrometry after Microwave Digestion

为探讨南阳彩色小麦中硒的含量,以偃麦4110为对照,用硝酸-高氯酸混酸和微波密闭罐压力消解样品,用断续流动法进样,利用KBH4酸性体系氢化物发生原子荧光光谱(HGAFS)法进行测定。结果表明:设定条件下,硒标准溶液在0～24μg/L质量浓度范围内呈良好的线性关系,r=0.9996;样品加标平均回收率为99.42%,平行测定的相对标准偏差为2.6%(n=11);干基样品中硒含量的多少依次为:南阳灰麦>偃麦4110>南阳蓝麦>大紫麦>小紫麦。该法操作简单、消解过程硒不易挥发损失、测定时基体干扰少、适用性强。

An analytical method for the determination of selenium in Nanyang colored wheat was presented by intermittent flow-hydride generation （by using acidic KBH4 system）-atomic fluorescence spectrometry （HGAFS） after microwave digesiton with nitric acid-perchloric acid. Under optimized conditions, the calibration curve of selenium standard solution showed a good linear relationship over the range of 0--24 μg/L （r = 0.9996）. The average recovery for spiked sampled was 99.42%, and a relative standard deviation （RSD） of 2.6% was obtained from 11 parallel determinations. Five wheat cultivars were ranked in decreasing order of selenium content （on a dry matter basis）： Nanyang grey, Yanmai 4110, Nanyang blue, large purple and small purple. The method was characterized by simple operation, low volatile loss of selenium during sample digestion, low matrix interference and high applicability.