Magnetic nanofluid based on hydrophobic deep eutectic solvent for efficient and rapid enrichment and subsequent determination of cinnamic acid in juice samples: Vortex-assisted liquid-phase microextraction

A quick, environmentally friendly and easy approach for the determination of cinnamic acid in juice samples based on the creation and usage of a novel magnetic nanofluid (mixture of hydrophobic deep eutectic solvent and magnetic nanoparticles) has been reported. Response surface methodology was applied to justify the contribution of the efficient factors including pH, nanofluid volume, ionic strength and vortex time. Cinnamic acid concentrations were monitored and quantified based on their HPLC peak representing linear correlations under the best operational circumstances showing linearity between 3 and 550 ng mL-1. The LOD, LOQ, and enrichment factor for cinnamic acid were 0.8 ng mL-1, 2.7 ng mL-1 and 57.2, respectively. The proposed method was used for enrichment and subsequent determination of cinnamic acid from juice samples which suggests a potential alternative approach for cinnamic acid analysis in complicated food samples.