Determination of Tamoxifen and Letrozole in Sewage by Solid Phase Extraction and Ultra Performance Liquid Chromatography/ Tandem Mass Spectrometry / 分析化学

ABSTRACT

Tamoxifen and letrozole are two of the most effective pharmaceuticals mainly used in hormonal dependent) breast cancer therapy. A trace analytical method using ultra performance liquid chromatography/tandem mass spectrometry(UPLC-MS/MS) was developed to simultaneously detect these two drugs in both influent) and effluent of municipal sewage treatment plant. Sewage samples were passed through an Oasis HLB cartridge, then an amino solid phase extraction cartridge was connected with Oasis HLB cartridge. Target compounds) was firstly eluted with 6 mL methanol and then 3 mL methanol was used to elute the amino solid phase extraction cartridge, collected and pooled the elutants. After concentration, target compounds were separated) on a BEH C_(18)) column using a gradient elution profile with a mobile phase consisting of 0.1% formic acid aqueous) solution and acetonitrile and detected by an electro spray ionization tandem mass spectrometry with multiple reactions monitoring(MRM). Satisfactory linearity(R~2>0.997) was obtained over the range of 1.0-100 μg/L) and 0.1-100 μg/L for tamoxifen and letrozole, respectively, with limits of quantification(LOQ) of 1.0 and 0.1 ng/L. Mean recoveries of two target compounds(spiked in sewage samples at three concentration levels) ranged from 68.8% to 103.0%, with relative standard deviations(RSD) less than 15%. This method can be applied for the analysis of target drugs sewage samples.