Determination of formaldehyde in fruit juice based on magnetic strong cation-exchange resin modified with 2,4-dinitrophenylhydrazine

► In this work, the MSCX resin modified with DNPH was synthesised. ► Extraction and derivatization were carried out in a single step. ► The MSCX resin adsorbing derivative was easily collected by external magnetic field. ► These resins can be reused 10 times.