A liquid chromatography method with single quadrupole mass spectrometry for quantitative determination of indomethacin in maternal plasma and urine of pregnant patients

► The LC-MS quantitative method of indomethacin was developed and validated in human maternal plasma and urine samples. ► Selectivity, sensitivity and reproducibility were achieved by using an in-source fragmentation technique. ► The lower limit of quantification of indomethacin is less than 14.8 ng/mL in maternal plasma and 10.5 ng/mL in human urine samples. ► The validated method has been used to determine indomethacin concentrations in samples of plasma and urine from pregnant patients.