Deep eutectic solvent-based iron nanoparticles coated by N, S-doped amorphous carbon and its application in magnetic Dμ-SPE combined with DLLME for the extraction of PAHs in eyeliner

This work presents a preparation of new magnetic nanoparticles coated with amorphous carbon and their application in dispersive solid-phase extraction in simultaneous extraction of sixteen polycyclic aromatic hydrocarbons from eyeliner. The extraction procedure was hyphenated with a lower density than water dispersive liquid-liquid microextraction (DLLME) for further preconcentration of the analytes to sensitive determination of them with gas chromatography-flame ionization detection. The magnetic adsorbent was prepared sonically from iron pentacarbonyl and then the nanoparticles were coated by N, S-doped amorphous carbon and the deep eutectic solvent prepared from tetrabutyl ammonium chloride and decanoic acid. The magnetic properties of the nanoparticles were studied by vibrating sample magnetometer. Also, scanning electron microscopy was used to investigate the nanoparticles morphology. The extraction procedure was done by migration of the analytes from eyeliner into a proper aqueous solution and their adsorption onto the nanoparticles. Then, the analytes were eluted and more concentrated by the DLLME approach. After validating the method, acceptable limit of detection and broad linear range were accessed in the ranges of 0.25-0.54 and 1.8-250 ng/g, respectively. Relative standard deviation values were <= 7.1% for the repeated analyses in the same day (n = 6) and different days (n = 6). Extraction recovery of the method was in the range of 79-96%. The introduced method was successfully used for the analysis of the PAHs in five eyeliner samples and only two of them were identified in all samples at ng/g level.