Midazolam determination by gas chromatography, liquid chromatography and gas chromatography--mass spectrometry.

Midazolam is determined in serum by gas chromatography with a nitrogen-selective detector, by liquid chromatography, and by gas chromatography--mass spectrometry. Comparable results are obtained with the three techniques with a within-run precision of 9% by gas chromatography and gas chromatography---mass spectrometry and 5% by liquid chromatography. Between-run precision is 13% by gas chromatography--mass spectrometry and 10% by liquid chromatography. Comparison of patient's sera by gas chromatography (x), liquid chromatography (y), and by gas chromatography (x), gas chromatography--mass spectrometry (y) gave correlations of 0.98 and 0.89, respectively. Interferences observed when using one technique, for example liquid chromatography, can be eliminated by analyzing the sample extract with one of the other techniques.