Abstract
A new magnetic graphene oxide (MGO) composite was developed as an adsorbent for the preconcentration of lenalidomide (LND) by ultrasound-assisted solid-phase extraction (UA-SPE) prior to determination by high-performance liquid chromatography with ultraviolet detection (HPLC-UV). The adsorbent was fabricated through chemical functionalization of a new surface-active ionic liquid (SAIL), i.e. 1-methyl-3-(trimethoxysilyl propyl)-imidazolium dodecyl sulfate (TMES-Im-DS) on MGO. The synthesized material presented the benefits of excellent adsorption for LND. The characterization of the synthesized functionalized magnetic nanocomposite was performed by Fourier transform-infrared spectroscopy, field emission scanning electron microscopy, Brunauer–Emmett–Teller (BET), vibrating sample magnetometry, and energy-dispersive X-ray spectroscopy. After optimization of the parameters, the limits of detection (LOD) and limit of quantification (LOQ) were 0.2 and 0.8 µg L−1 and 0.6 and 2.5 µg L−1in water and plasma samples, respectively. The enrichment factors (EFs) were from 90 to 180 in the samples. The relative standard deviation (RSD%, n = 5) as intra- and inter-day precision were from 6.3% to 7.5% and 7.1% to 8.5% in water and plasma, respectively. Lastly, the developed method presented good results for the preconcentration of LND in plasma with satisfactory repeatability.
Acknowledgments
The support of this investigation by the Standard Research Institute is gratefully acknowledged.