Application of D-limonene as a bio-based solvent in low density-dispersive liquid-liquid microextraction of acidic drugs from aqueous samples

This study deals with the application of different monoterpenes as relatively green bio-based solvents for low densitydispersive liquid-liquid microextraction (LD-DLLME) of different non-steroidal anti-inflammatory drugs (NSAIDs) from aqueous samples in comparison with conventional halogenated solvents. Results indicated that D-limonene could extract the hydrophobic compounds with higher %recovery compared with other bio-based and halogenated solvents. The LDDLLME procedure was optimized by applying one-factor-at-a-time (OFAT) followed by central composite face-centered design (CCF) of the response surface methodology (RSM). Under the optimal conditions, the method exhibited good linearity with r ≥ 0.9950 with low LOD as well as LOQ levels in the range of 0.11 to 0.81 and 0.36 to 2.69 ng/mL, respectively. The method was efficiently applied to a variety of real aqueous samples. Finally, the green aspect of our procedure was compared with some reported methods using two green metric tools.