Determination of triazine herbicides from water, tea, and juice samples using magnetic dispersive micro-solid phase extraction and magnetic dispersive liquid-liquid microextraction with HPLC

A novel, environmentally friendly, and efficient method for determining triazine herbicides in water, tea, and juice was developed by combining magnetic dispersive micro-solid phase extraction (MD-μSPE) with magnetic dispersive liquid-liquid microextraction (MDLLME), followed by high-performance liquid chromatography (HPLC). The pretreatment process, utilized magnetic biochar (MBC) and magnetic deep eutectic solvent (MDES) as the adsorbent and extractant, respectively. Fe(NO 3 ) 3 was loaded onto waste mushroom sticks to prepare MBC via impregnation-pyrolysis, while tri- n -butylphosphine oxide, nonanoic acid, and FeCl 3 were combined through hydrogen bonds to form MDES. This approach significantly reduced environmental impact using waste materials and shortened separation times. The method demonstrated excellent linearity (1–100 μg L −1 ), low detection limits (0.3 μg L −1 ), and good precision (RSDs <6.5 %). Recoveries in water, tea, and juice ranged from 80.1 % to 90.6 %. This combined MD-μSPE-MDLLME approach offers a greener and more efficient extraction process for separating and concentrating pesticides from complex food samples.