Magnetic Retrieval of Ionic Liquids: High Sensitivity Fluorescence Determination of Carvedilol in Tablets, Plasma, and Urine

ABSTRACT

Ionic liquid-based dispersive liquid–liquid microextraction with magnetic dispersive micro-solid phase extraction was employed to determine carvedilol, an anti-arrhythmic drug, with fluorescence detection. The ionic liquid extractant was magnetically retrieved with unmodified nanoparticles. The 1-Octyl-3-methylimidazolium hexafluorophosphate was used to extract the analyte. Magnetite nanoparticles were added to adsorb the ionic liquid. The loaded magnetite nanoparticles were collected by a magnetic field. The ionic liquid and carvedilol were recovered from the surface of the magnetite nanoparticles by sonication in the presence of ethanol. The analyte was determined by fluorescence with excitation at 244 nm and emission at 355 nm. Under the optimized conditions, the calibration graph was linear from 0.4 ng mL⁻¹ to 80 ng mL⁻¹ with a detection limit of 0.1 n g mL⁻¹. The relative standard deviation for carvedilol was 1.57%. The method was used to determine the analyte in tablets, human plasma, and urine with recoveries between 95.04 and 106.6%.

KEYWORDS:

• Carvedilol
• dispersive liquid–liquid microextraction
• fluorescence
• ionic liquid
• magnetic dispersive micro-solid phase extraction