Mixed hemimicelle magnetic dispersive solid-phase extraction using carbon-coated magnetic nanoparticles for the determination of tramadol in urine samples.

Ionic liquid carbon-coated magnetic nanoparticles were successfully applied as an adsorbent in a mixed hemimicelle magnetic dispersive solid-phase extraction method for the determination of tramadol from urine samples coupled with high-performance liquid chromatography with UV-vis detection. The significant parameters affect the extraction efficiency including type and amount of adsorbent, sample volume, pH, ionic strength, type and amount of elution solvent, time of extraction and desorption, time of ionic liquid loading on the adsorbent and stirring rate were studied and optimized. The proposed method provided a fast, straightforward, environmentally friendly and adsorbent recyclable approach for tramadol analysis. The linear range for the tramadol determination was from 100 to 1500 ng/mL. Precisions and accuracies were within 6%. The applicability of the proposed method in clinical trial was tried successfully on determination of tramadol in addicted subjects under tramadol therapy. The mean percent recovery of the patient samples was 94%. The results proved that the proposed method could be applied in clinical and forensic laboratories for determination of tramadol from biological urine samples.