This application note describes a method for analyzing pharmaceuticals in water using solid-phase extraction (SPE) and liquid chromatography/tandem mass spectrometry (LC/MS/MS) in both positive and negative ion modes. Good linearity was observed for analytes from 1 pg to 1 ng on column. Repeatability from six injections of analytes at 5 pg on column showed RSDs below 15%, for all target compounds except for fluoxetine at 23%.
This document details an analytical method for detecting trace levels of pharmaceuticals in water samples. The procedure utilizes Solid Phase Extraction (SPE) with Oasis HLB cartridges followed by analysis via Agilent 1200 LC coupled with a G6410A Mass Spectrometer. The method covers 19 compounds in positive ion mode and 11 in negative ion mode, achieving detection at low picogram levels without derivatization.
| Column | ZORBAX Extend-C-18, RRHT, 2.1 mm x 100 mm, 1.8 µm |
|---|---|
| Column temperature (Negative) | 60°C |
| Flow rate | 0.3 mL/min |
| Injection volume | 1.0 µL |
| Mass range (Positive) | 125 to 800 amu |
| Mass range (Negative) | 120-800 amu |
| Scan time | 300 ms |
| Capillary voltage | 3500 V |
| Drying gas flow | 9 L/min |
Nineteen pharmaceuticals are analyzed in positive ion mode.
Good linearity was observed for analytes from 1 pg to 1 ng on column.
Repeatability showed RSDs below 15% for all target compounds except fluoxetine.