Monitoring biogenic amines in cream and cheese samples using liquid nitrogen-induced homogeneous liquid-liquid extraction combined with magnetic ionic liquid-based dispersive liquid-liquid microextraction and HPLC-DAD.

Abstract

In the current research, a sample pretreatment method termed liquid nitrogen-induced homogeneous liquid-liquid extraction combined with ionic liquid-based dispersive liquid-liquid microextraction was validated for the extraction of four biogenic amines from cream and cheese samples. Briefly, the sample was mixed with acetonitrile and deionized water in a tube, and the mixture was vortexed after adjusting its pH. The tube was then placed in liquid nitrogen, and the analytes were extracted into acetonitrile. Subsequently, the acetonitrile phase was collected, and after mixing with magnetic ionic liquid, the mixture was rapidly injected into deionized water. The extracted analytes were determined using high-performance liquid chromatography. Various parameters, including acetonitrile volume, vortexing time, sample solution pH, ionic strength, cooling time, and extraction solvent type and volume, were optimized using a one-factor-at-a-time method. For the considered biogenic amines, low limits of detection (0.89-1.25 ng g-1) and quantification (2.97-4.15 ng g-1), high extraction recoveries (68-83%), and good precision (relative standard deviations ≤ 5.3%) were attained using the proposed method. Finally, various cheese and cream samples were analyzed using the suggested method.