Synthesis of spindle-like amino-modified Zn/Fe bimetallic metal-organic frameworks as sorbents for dispersive solid-phase extraction and preconcentration of phytohormoes in vegetable samples

•The spindle-like Zn/Fe bimetallic MOF was prepared with high yield and high purity.•The morphology of NH2-Zn/Fe-MIL-88 can be rearranged by optimizing ratio of Zn2+/Fe3+.•NH2-Zn/Fe-MIL-88 was used as sorbent of dSPE to extract and enrich phytohormones.•The LODs of HPLC for analysis of phytohormones were achieved at 0.07–0.15 ng⋅mL−1.•Enrichment factors with NH2-Zn/Fe-MIL-88 as sorbent were obtained from 129 to 346.