Pigments and organic acids are among the most common impurities in complex sample matrices. Their presence in the samples often interferes with the detection of trace analytes. This study aimed to design and develop magnetic materials (GCB/Fe3O4-PSA) for the efficient purification of organic acids and pigment impurities in sample matrices. We employed the acid modification method to enhance the modification of magnetic Fe3O4 by the primary secondary amine adsorption group (PSA), effectively boosting its adsorption performance. This modification technique not only retains the inherent adsorption characteristics of Fe3O4 but also avoids the irreversible damage to Fe3O4′s own adsorption by traditional grafting methods. Subsequently, Fe3O4-PSA and graphitized carbon black (GCB) were combined through a simple physical assembly method to prepare GCB/Fe3O4-PSA, which was used for the purification of pigments and organic acids in complex matrices. During the purification process, GCB/Fe3O4-PSA can be rapidly magnetically separated. After six reuses, the adsorption performance remains above 80 %, fully demonstrating the rapid purification ability and reusability potential of GCB/Fe3O4-PSA. Compared with unmodified Fe3O4, GCB/Fe3O4-PSA significantly enhanced the purification effect of complex matrices. Its adsorption capacities for chlorophyll and ascorbic acid increased by 276.9 % and 263.9 % respectively. After combining with the GCB/Fe3O4-PSA purification material, cathinones in complex matrix samples (tea, apples, carrots) were determined using UPLC-MS/MS. The recoveries in spiked samples ranged from 96.35 % to 104.17 %, with the RSDs < 3.02 %. Simultaneously, characterization methods such as SEM, FTIR, XRD, VSM, XPS, and BET were used to study the surface structure and chemical composition of GCB/Fe3O4-PSA. The above results highlight the outstanding performance of GCB/Fe3O4-PSA in the efficient purification of organic acids and pigments in complex matrices and also show its considerable application potential in the pretreatment of complex matrix samples.