响应面优化超声提取-原子吸收光谱法测定贝类中铅的含量

在单因素实验基础上,采用Plackett-Burman筛选和中心组合设计实验筛选优化了超声时间、硝酸浓度和混酸体积三个因素对超声提取贝类中铅的影响。由响应面法建立二次回归模型得到最佳超声条件为:超声提取时间29 min,温度40℃,功率320 W,混酸HNO3（2.5 mol/L）-H2O2（3 mol/L）8.10 m L,铅的提取率最高为93.0%。方法的相对标准偏差（RSD）为5.83%,检出限为0.65μg/L,定量限为2.1μg/L。t检验结果表明超声提取法与湿消解法之间不存在显著性差异。超声提取法简便、温和安全且适用于贻贝等贝类样品中铅的提取。 

Determination of lead in shellfish by ultrasound assisted extraction-atomic absorption spectrometry with response surface method

The optimized extraction conditions of lead in shellfish were obtained by Plackett-Burman design and response surface methodology on the basis of single factor experiment. The results indicated that the extraction rate of lead was 93.0%when ultrasonic extraction time was 29 min, ultrasonic temperature was 40 ℃, ultrasonic power was 320 W, HNO3 ( 2.5 mol/L) -H2O2 ( 3 mol/L) 8.10 m L.The relative standard deviation was 5.83%, the limit of detection was 0.65 μg/L, limit of quantity was2.1 μg/L.The results of t test showed that there was no significant difference between the ultrasound assisted extraction and wet digestion method.The ultrasonic extraction is more convenient, safer and can also be applied to determination of lead in shellfish.