HPLC-FLD测定水中联苯胺的方法研究
2017-11-07张秀蓝任立军朱超飞杨文龙刘金林吴忠祥
张秀蓝,郭 婧,任立军,朱超飞,杨文龙,刘金林,吴忠祥,董 亮,杜 兵
国家环境分析测试中心,国家环境保护二英污染控制重点实验室,北京 100029
HPLC-FLD测定水中联苯胺的方法研究
张秀蓝,郭 婧,任立军,朱超飞,杨文龙,刘金林,吴忠祥,董 亮,杜 兵
探讨了利用液相色谱分离,荧光检测器测定地表水中联苯胺的可行性。前处理方法对比验证了液液萃取法和固相萃取法。水样在碱性条件下(pH=11~12)进行提取,当提取体积为1.0 L时,液液萃取液相色谱荧光法检测,方法检出限为1.4 ng/L,定量下限为5.5 ng/L;固相萃取液相色谱荧光法检测,方法检出限为0.9 ng/L,定量下限为3.6 ng/L。分别对地表水、生活废水、工业废水3种不同水体进行基体加标试验,加标浓度为10.0、40.0、80.0 ng/L。结果显示, 对于3种不同基体和不同加标浓度的水样, 两种方法均有较好的准确性和重现性,方法回收率为80%~120%, 相对标准偏差均小于20%, 满足《地表水环境质量标准》(GB 3838—2002)中对联苯胺的监测需求。
水体; 固相萃取法; 液液萃取法; 液相色谱分离;荧光测定; 联苯胺
Abstract:Due to the limiting value of benzidine in water, high performance liquid chromatography with fluorescence detector (HPLC-FLD) was employed to try to meet the monitoring demand. For the pretreatment, two classic methods—both liquid-liquid extraction and solid-phase extraction, were verified and compared. Under the condition of basic (pH=11-12), benzidine was extracted by methylene chloride from 1 L water, and detected by HPLC-FLD, the method detection limit (MDL) was 1.4 ng/L, and the quantitative limit was (QL) 5.5 ng/L; With the same instrument conditions, the MDL and QL were 0.9 and 3.6 ng/L for solid phase extraction method. In order to test the accuracy and precision of these two methods, three kinds of matrix spiking were proceeding. While, the water types were surface water, wastewater and industrial wastewater, and the standard were added 10.0, 40.0 and 80.0 ng/L, respectively. According to the results, for both methods had good accuracy and reproducibility, recoveries were between 80%-120%, and relative standard deviations were less than 20%. It’s confirmed that HPLC-FLD was an effective way to monitor benzidine in water.
Keywords:water;solid phase extraction;liquid-liquid extraction;liquid chromatographyseparation;fluorescence detection;benzidine
联苯胺(图1)是4,4′-二氨基联苯的俗称, 国际癌症研究机构(IARC)将其列属于第一类致癌物质。我国对联苯胺的水环境浓度要求严苛,《地表水环境质量标准》(GB 3838—2002)规定地表水中联苯胺限值为0.000 2 mg/L[1]。检测方法参考《水和废水标准检验法》(第15版)[2], 气相色谱法, 最低检出限为0.000 2 mg/L。联苯胺的检测方法还包括:分光光度法[3], 检出范围在0~4.0 mg/L; 液相色谱法[4], 检出限为0.14 ng/mL(即0.14 μg/L); 液相色谱串联质谱法[5], 检出限为0.09 μg/L。上述方法中仅有液相色谱串联质谱法可满足我国对联苯胺的要求。……
