在线双向萃取流动注射仪快速测定餐(饮)具中阴离子合成洗涤剂残留量

Rapid determination of anionic synthetic detergent residue in tableware by online flow injection method with two-way extraction

目的建立在线流动注射分析仪测定餐(饮)具中阴离子合成洗涤剂残留量的快速检测方法。方法分别对餐(饮)具进行样液制备。配制质量浓度为0.025~1.000mg/L的十二烷基苯磺酸钠标准溶液,采用在线双向萃取流动注射法对样液定量分析。优化进样条件,去除干扰物质,使仪器在最优的状态下进行测量,并对分析方法的精密度、准确度、加标回收率进行评价。结果 55份样品中,检测合成洗涤剂阳性8份,检出率为14.5%,含量为0.093~1.778mg/L,检出阳性样品为碗、汤匙、筷子。在0.025~1.000mg/L质量浓度范围内,阴离子合成洗涤剂标准系列呈现良好的线性关系,回归方程y=2.62×10^(-5) x-1.62×10^(-1),相关系数r=0.999 7。方法检出限为0.001 5mg/L,相对标准偏差(RSD)为1.1%~4.7%,2种标准样品的加标回收率为95.0%~101.0%。结论该方法简便、安全、准确度和精密度高,适用于大批量样品的测定。

Objective To establish a fast method for determination of anionic synthetic detergent residue in tableware by online flow injection analysis.Methods The tableware sample solutions were prepared.Standard anionic surfactant solution series of mass concentration range from 0.025 to 1.000 mg/L were prepared.The sample solution was quantitatively analyzed by online two-way extraction flow injection method.The injection conditions were optimized and the interfering substances were removed,the instrument was operated under the optimal state to perform measurement.The precision,accuracy and recovery rate of the established analytical method were evaluated.Results A total of 55 samples were analyzed,among which 8 were positive for synthetic detergent,resulting the detection rate of 14.5%,the detected mass concentration were in the range of 0.093-1.778 mg/L,the positive samples were bowls,spoons and chopsticks.In the concentration range of 0.025-1.000 mg/L,the standard series of anionic synthetic detergents showed a good linear relationship.The linear regression equation was y=2.62×10^(-5) x-1.62×10^(-1),with the correlation coefficient r of 0.999 7.The detection limit of the method was 0.001 5 mg/L,the RSDs were in the range of 1.1%-4.7%,the standard recovery of the two standard samples were in the range of 95.0%-101.0%.Conclusion The established method is simple,safe,with high accuracy and precision,which make it suitable for the determination of large quantities of samples.