石墨炉原子吸收分光光度法测定茵栀黄注射液及其中的铅镉

GFAAS Determination of Pb and Cd in Yin Zhi Huang Injection

采用石墨炉原子吸收分光光度法(GFAAS),通过对波长、光谱带宽、灯电流、干燥温度、灰化温度、原子化温度的选择来确定最佳条件,直接测定经浓HNO3和H2O2消解法预处理的茵栀黄注射液及4味药材金银花、茵陈、栀子、黄芩中Pb、Cd的含量。用体积分数为0.002%柠檬酸作基体改进剂,提高了灰化温度,消除了背景干扰,改善了原子化吸收峰,提高了测定灵敏度。线性回归方程为APb=0.0033c+0.04072,相关系数为rPb=0.9991,检出限为4×10-8mg/L;ACd=0.0889c+0.2158,rCd=0.9995,检出限为2×10-9mg/L。方法回收率为99.0%～110%,相对标准偏差小于2.5%。

The samples for GFAAS analysis were pretreated by digesting with concentrated nitric acid and hydrogen peroxide. The best conditions were confirmed by the investigation of wavelength, spectral width, lamp-current, dry temperature, ashing temperature and atomization temperature, so the contents of Pb and Cd in Yin zhi huang injection and four medicinal materials were determined by GFAAS. 0. 002% citric acid was used as matrix modifier to increase the ashing temperature, eliminate the background interference, improve the atomy absorption peak and enhance the sensitivity. The linear regression equation, the correlation coefficient and the detection limit are：APb =0. 003 3C ＋0. 040 72, rPb =0. 999 1, 4 × 10^-8 mg/L; ACd =0. 088 9C ＋ 0. 215 8, rCd= 0. 999 5, 2 × 10^-9 mg/L, respectively. The recoveries of this method are in a range of 99.0% 110%, with a RSD＇ value of less than 2. 5%. This method is proved to be simple, rapid and high accuracy with satisfactory results, and it can provide a simple and reliable method for the determination of trace elements in the Chinese traditional medicine.