流动注射在线预富集-高效液相色谱法测定水中的4-壬基酚和双酚A

Determination of 4-Nonylphenol and Bisphenol A in Water Samples by High Performance Liquid Chromatography Coupled with On-line Flow Injection Preconcentration

建立了以香烟过滤嘴作吸附剂,在线固相萃取(SPE)与高效液相色谱(HPLC)联用测定水中双酚A(bisphenol A,BPA)和4-壬基酚(4-nonylphenol,4-NP)的方法。对于高效液相(HPLC)在线固相萃取而言,采用内置香烟过滤嘴的预富集圆形柱来代替传统的高效液相仪中的注射管进样环用于在线固相萃取。通过流动注射仪将样品分析物负载加入到预富集柱中,随后采用V(甲醇):V(H2O)=93:7混合液为洗脱剂对富集的样品分析物进行洗脱。采用Eclipse XDB-C18色谱柱,V(甲醇):V(H2O)=93:7混合液为流动相,流速为1.0mL/min,紫外检测波长为227nm,保留时间定性,外标法定量。双酚A在0.005～0.8mg/L、4-壬基酚在0.04～8.0mg/L范围内,两者峰面积与浓度呈线性关系,相关系数分别为0.9985和0.9983,检出限(S/N=3)分别为2.1和10.0μg/L,富集倍数分别为816和346倍。对标准混合物(BPA:0.2mg/L;4-NP:2.0mg/L)重复测量11次的相对标准偏差为2.3%和1.5%。本方法用于当地河流水样中BPA和4-NP的测定,回收率为93.2%～105.4%。

An on-line solid phase extraction（SPE） protocol using the cigarette filter as sorbent coupled with high performance liquid chromatography（HPLC） was developed for the simultaneous determination of trace bisphenol A（BPA） and 4-nonylphenol（4-NP） in water samples.To on-line interface solid phase extraction to HPLC,a preconcentration column packed with the cigarette filter was used to replace a conventional sample loop on the injector valve of the HPLC for on-line solid phase extraction.The sample solution was loaded and the analytes were then preconcentrated onto the preconcentration column.The collected analytes were subsequently eluted with a mobile phase of methanol-water（93∶7）.Chromatographic column Eclipse XDB-C18 was used with methanol-water（93∶7） as mobile phase.The flow rate was 1.0 mL/min and the detected wavelength was set at 227 nm.The analytes were qualitated by retention time and quantitated by peak area using external standard method.There was excellent linearity between peak area and concentration of analytes in the concentration range of 0.005-0.8 mg/L for bisphenol A and 0.04-8.0 mg/L for 4-nonylphenol,the correlation coefficients were 0.9985 and 0.9983 respectively.The detection limits（S/N=3） of sample solution were 2.1 μg/L and 10.0 μg/L,respectively.The enhancement factors were 816 and 346.The relative standard deviations for eleven replicate measurements of a standard mixture（BPA：0.2 mg/L;4-NP：2.0 mg/L） were 2.3% and 1.5%,respectively.The developed method was applied to the determination of trace BPA and 4-NP in local river water samples.The recoveries were 93.2%-105.4%.