SPE-HPLC法测定城市污水中8种四环素类抗生素

Determination of Eight Tetracyclines in Municipal Wastewater by SPE-HPLC

建立了一种固相萃取(solid phase extraction,SPE)-高效液相色谱(high performance liquid chromatography,HPLC)法同时测定城市污水中8种四环素类抗生素的分析方法。对色谱条件进行了优化,结果表明,在350 nm的检测波长下,以甲醇-乙腈(2∶3)为流动相A,0.1%三氟乙酸(p H=2.0,含0.01 mol/L草酸铵)为流动相B,流动相之比为2∶3时,8种抗生素的分离效果最好。对固相萃取条件进行了优化,结果表明,采用HLB固相萃取柱,调节样品p H=2,以3 m L 0.1%三氟乙酸-甲醇溶液洗脱,8种四环素类抗生素的加标回收率达到了77.4%~113.3%,相对标准偏差为1.5%~9.9%。3倍信噪比下,8种四环素类抗生素的检出限为1.61~12.50 ng/L。采用此方法对北京某污水处理厂进水进行检测,8种四环素类抗生素均有检出,浓度范围为0.10~1.90μg/L。

A new method was developed for simultaneously determining eight species of tetracyclines in municipal wastewater by solid phase extraction（SPE） and HPLC analysis,and chromatographic conditions were optimized as well.It was found that eight species of tetracyclines were effectively separated at UV wavelength of 350 nm with a mobile phase consisting of the mixture of methyl alcohol and acetonitrile（A）,and with 0.1% trifluoroacetic acid in water（B） in proportion of A∶B=40∶60（V/V）.Furthermore,SPE conditions were optimized,and the results showed that enriched by HLB and purified by 0.1% trifluoroacetic acid in methyl alcohol,the recoveries of eight tetracyclines in municipal wastewater could reach the range of 77.4%～113.3% and the relative standard deviations（RSD） were 1.5%～9.9%;and the limits of detection for eight tetracyclines were1.61～12.50 ng/L.Consequently,the method has been applied to determination of tetracyclines in the influent sewage of a wastewater treatment plant in Beijing,the results indicated that all of the eight species of tetracyclines were detected and the concentrations were in the range of 0.10～1.90 μg/L.