Use of magnetic ionic liquid for selective extraction of proline from wine and honey samples

A simple, cheap, green and novel air-assisted magnetic ionic liquid-based liquid phase microextraction (AA-MIL-LPME) method was developed for the selective extraction, accurate and sensitive determination of proline from wine and honey samples. Two different magnetic ionic liquids (MILs) were prepared to be investigated for use in the AA-MIL-LPME method. The accuracy of the method was evaluated using the standard addition method and comparing it with the reference method. Experimental parameters such as MIL volume, pH, amount of KCl, extraction cycle, and sample volume were optimized by Plackett-Burman design. Under optimized conditions, limits of detection and quantification of the AA-MIL-LPME method was calculated as 12.1 μg L^-1 and 40 μg L^-1, respectively. Relative standard deviation for 100 μg L^-1 of proline (N = 10) was 3.8 %., the linear range of the method was 40-800 μg L^-1 with an enrichment factor of 250. The AA-MIL-LPME method was easily applied for the determination of proline from complex sample matrices such as honey and wine by using an UV-VIS spectrophotometer.