地表水超痕量苯并(a)芘的检测及空白干扰消除

Determination of Ultra-trace Benzo (a) pyrene in Surface Water and Elimination of Blank Interference

采用液液萃取-超高效液相色谱仪接荧光检测器测定地表水中超痕量的苯并(a)芘,并对方法空白的干扰因素进行探讨。研究发现,该法的空白干扰主要来自于溶剂二氯甲烷,溶剂经蒸馏提纯后可消除干扰。以重新蒸馏提纯的二氯甲烷为提取剂,方法的检测限为0.05 ng/L,加标回收率为87.4%~132%,且空白测定值低于方法检出限,可满足地表水中超痕量苯并(a)芘检测的需求。

This research adopts the liquid-liquid extraction /ultra high performance liquid chromatography coupled with fluorescence detector for the determination of ultra-trace benzo（ a） pyrene in surface water. And the interference factors of blank are discussed. The research shows that dichloromethane containing a small amount of benzo （ a） pyren is the main factor leading to blank interference, and solvent redistillation can remove interference. By using the purified dichloromethane, the detection limit is 0. 05 ng/L, and the recovery rate was 87. 4% -132%. The blank value was lower than the detection limit. The method can be used for the quantitative detection of ultra trace amounts of benzo（ a） pyrene in water.