Thickness-controllable synthesis of metal-organic framework based hollow nanoflowers with magnetic core via liquid phase epitaxy for phosphopeptides enrichment

A thickness-controllable method for preparing metal-organic framework hollow nanoflowers on magnetic cores (Fe3 O4 @MOFs HFs) was demonstrated for the first time. The petal of magnetic core with hollow nanoflower structure served as medium for assembling UiO-66-NH2 shell with different thickness. To further improve its performance, Zr4 + was immobilized on the surface of Fe3 O4 @UiO-66-NH2 . Compared with conventional Fe3 O4 @UiO-66-NH2 -Zr4 + nanospheres, the Fe3 O4 @UiO-66-NH2 -Zr4 + HFs showed increased enrichment performance for phosphopeptides. The Fe3 O4 @UiO-66-NH2 -Zr4 + HFs served as an attractive restricted-access adsorption material exhibited good selectivity ( m beta -casein : mBSA = 1:10 0 0), high sensitivity (1.0 fmol) and excellent size-exclusion effect ( m beta-casein digests : mBSA = 1:200). Furthermore, the Fe3 O4 @UiO-66-NH2 -Zr4 + HFs was successfully applied to the specific capture of ultratrace phosphopeptide from complex biological samples, revealing the great potential for the identification and analysis of trace phosphopeptides in clinical analysis. This work can be easily extended to the fabrication of diverse mag-MOF HFs with multifunctional and easy to post-modify properties, and open up a new avenue for the design and construction of new MOFs material. (c) 2025 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.