Sample preparation is a fundamental step in the proteomics and peptidomics workflow. Due to their good biocompatibility, superparamagnetic property, and high binding capacity, magnetic nanoparticles (MNPs) functionalized with different active moieties have been widely applied in recent years in various sample preparation procedures in proteomics and peptidomics analysis. The magnetic cores of the MNPs facilitate elegant handling using only magnetic devices and their small diameters are advantageous for increasing the sensitivity when using subsequent mass spectrometry (MS) analysis or gel electrophoresis. This review mainly focuses on overviewing present advances in the preparation and application of functionalized magnetic nanoparticles for sample preparation in proteomics and peptidomics analysis, including protein digestion, enrichment of low-abundance peptides/proteins and specific enrichment of peptides/proteins with post-translational modifications, such as phosphorylation and glycosylation.

In this work, polydopamine (PDA)-coated magnetic microspheres with surface modification of zirconium-based MOFs were synthesized for the first time. The as-synthesized Fe₃O₄@PDA@Zr-MOF composites were successfully applied as a novel immobilized metal ion affinity platform for phosphoproteome research.

In this work, for the first time, Ti⁴⁺–Fe₃O₄@polydopamine microspheres were designed and synthesized for efficient and selective enrichment of phosphopeptides in biological samples.