Determination of acetochlor by UPLC-MS³ in cells and its application to a cellular pharmacokinetic study

The aim of this work was to develop a fast, simple, and reliable UPLC-MS³ method for the sensitive detection of acetochlor in biological samples. In MS³ mode, the ion transition m/z 270.1 → 224.1→148.1 was chosen for quantification with butachlor as the internal standard. In the UPLC system, separation was performed on a UPLC column (2.1 × 50 mm ID, 1.7 μm) with 0.1 % FA in water and acetonitrile as mobile phases. After simple protein precipitation via acetonitrile, the method was well validated with good linearity (0.5-20 ng/mL, r > 0.995), accuracy (-3.70 %-2.98 %), and precision (<15 %). The selectivity and sensitivity were improved obviously in MS³ mode than that in MRM mode. The developed UPLC-MS³ method was successfully applied to the cellular pharmacokinetics study of acetochlor in MCF-7 cells.