Supramolecular microextraction combined with paper spray ionization mass spectrometry for sensitive determination of tricyclic antidepressants in urine

• Published in: Analytica chimica acta 2020-04, Vol.1106, p.52-60
• Main Authors: Oliveira, Fernanda Midori de, Scheel, Guilherme Luiz, Augusti, Rodinei, Tarley, César Ricardo Teixeira, Nascentes, Clésia Cristina
• Format: Article
• Language: English
• Subjects: Microextraction; Paper spray ionization; SUPRAS; Tricyclic antidepressants; Urine
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2020.01.061

This work describes a novel methodology to analyze four tricyclic antidepressants (amitriptyline, doxepin, imipramine and, nortriptyline) in urine samples by combining supramolecular microextraction and paper spray ionization mass spectrometry (PS-MS). The proposed method uses a supramolecular solvent in which reverse micelles of 1-decanol are dispersed in tetrahydrofuran (THF)/water. The extraction of the tricyclic antidepressants at pH 9.0 requires a sample volume of 10.0 mL, short extraction time (1.0 min of extraction and 5 min of centrifugation), low amounts of organic solvent (50 μL of 1-decanol and 200 μL of THF), and provides high preconcentration factors: 96.9 to amitriptyline, 93.6 to doxepin, 71.3 to imipramine, and 146.9 to nortriptyline. The quantification by PS-MS is fast and straightforward because chromatographic separation is not required and all analytes were determined simultaneously. The limits of detection (LOD), quantification (LOQ), and the precision (RSD, %) of the developed method ranged between 5.2 and 8.6 μg L−1, 17.4–28.7 μg L−1 and 1.3–12.9%, respectively. Urine samples of five individuals (three males and two females) were used for accuracy evaluation. The accuracy obtained in these spiked urine samples at μg L−1 levels varied from 95.3 to 112.0%. The method also provided clean mass spectra with a high signal-to-noise ratio, which demonstrates the analytical appeal combination of supramolecular microextraction with determination by paper spray mass spectrometry. [Display omitted] •Supramolecular microextraction provided gain in sensitivity and sample’s clean-up.•The method presented high preconcentration factors for TCAs in urine.•PS-MS was used to TCA’s quantification by internal standard calibration.•PS-MS analyses were fast and without interference from the sample matrix.•The method employed minimal sample and solvents volumes.