Polydimethylsiloxane/polypyrrole stir bar sorptive extraction and liquid chromatography (SBSE/LC-UV) analysis of antidepressants in plasma samples

• Published in: Analytica chimica acta 2009-02, Vol.633 (1), p.57-64
• Main Authors: Melo, L.P., Nogueira, A.M., Lanças, F.M., Queiroz, M.E.C.
• Format: Article
• Language: English
• Subjects: Adsorption; Analytical chemistry; Antidepressive Agents - blood; Chemistry; Chromatographic methods and physical methods associated with chromatography; Chromatography, Liquid - methods; Dimethylpolysiloxanes - chemical synthesis; Exact sciences and technology; Hydrogen-Ion Concentration; Liquid chromatography; Other chromatographic methods; Plasma sample; Polydimethylsiloxane; Polymers - chemical synthesis; Polypyrrole; Pyrroles - chemical synthesis; Reproducibility of Results; Solid Phase Extraction - methods; Stir bar sorptive extraction; Temperature; Time Factors
• ISSN: 0003-2670; 1873-4324
• DOI: 10.1016/j.aca.2008.11.042

A new polymeric coating consisting of a dual-phase, polydimethylsiloxane (PDMS) and polypyrrole (PPY) was developed for the stir bar sorptive extraction (SBSE) of antidepressants (mirtazapine, citalopram, paroxetine, duloxetine, fluoxetine and sertraline) from plasma samples, followed by liquid chromatography analysis (SBSE/LC-UV). The extractions were based on both adsorption (PPY) and sorption (PDMS) mechanisms. SBSE variables, such as extraction time, temperature, pH of the matrix, and desorption time were optimized, in order to achieve suitable analytical sensitivity in a short time period. The PDMS/PPY coated stir bar showed high extraction efficiency (sensitivity and selectivity) toward the target analytes. The quantification limits (LOQ) of the SBSE/LC-UV method ranged from 20 ng mL −1 to 50 ng mL −1, and the linear range was from LOQ to 500 ng mL −1, with a determination coefficient higher than 0.99. The inter-day precision of the SBSE/LC-UV method presented a variation coefficient lower than 15%. The efficiency of the SBSE/LC-UV method was proved by analysis of plasma samples from elderly depressed patients.