Determination of morphine and oxymorphone in exhaled breath condensate samples: Application of microwave enhanced three-component deep eutectic solvent-based air-assisted liquid-liquid microextraction and derivatization prior to gas chromatography-mass spectrometry.

In this work, a microwave-enhanced air-assisted liquid-liquid microextraction method combined with gas chromatography-mass spectrometry has been developed for morphine and oxymorphone assessment in EBC samples. For this purpose, choline chloride-menthol-phenylacetic acid deep eutectic solvent (as an extraction solvent), butyl chloroformate (as a derivatization agent), and picoline (as a catalyst) are used. After performing predetermined extraction cycles in the microextraction method, the obtained cloudy solution is exposed to microwave irradiations to enhance extraction and derivatization efficiencies. The method provided low limits of detection (morphine 2.1 and oxymorphone 1.5 ng mL) and quantification (morphine 7.2 and oxymorphone 5.2 ng mL) in the EBC samples. The method had proper repeatability, accuracy, and stability expressed as relative standard deviations less than 5.1, 9, and 9%, respectively. The developed method was successfully used to determine morphine and oxymorphone concentrations in the EBC samples of addict patients.