Synthesis of Magnetic Nanomaterials with Mixed Lanthanide Metals And its application in phosphopeptide enrichment

Abstract

In this study, DOTA was used as a ligand to develop a magnetic IMAC material capable of supporting mixed lanthanide metal ions (Tb³⁺, Tm³⁺, Ho³⁺, Lu³⁺), Fe₃O₄@TCPP-DOTA-M³⁺, and used for phosphopeptide enrichment. First, the amino-modified magnetic nanomaterial covalently bonds the hydrophilic linking arm TCPP (tetracarboxys(4-carboxylphenyl)porphyrin) and DOTA to the surface of the material through ethylenediamine, and then simultaneously immobilizes various lanthanide metal ions on the material. Surface synthesis of new magnetic nanomaterials. The new material was subjected to phosphorylation proteomic analysis of the standard protein α-casein-cut product, the mixture of α-casein-cut product and BSA-cut product (1:100), and the complex biological sample digestion products. The functionalized magnetic nanomaterial Fe₃O₄@TCPP-DOTA-M³⁺ (Tb³⁺, Tm³⁺, Ho³⁺, Lu³⁺) mixed with lanthanide metal realizes the specific enrichment and separation of phosphopeptides. The introduction of TCPP and DOTA increases the hydrophilicity, stability and metal ion loading of the material, so that the newly developed mixed lanthanide metal ion-loaded magnetic nanomaterials are not only superior to single-tethered metals. The phosphopeptide enrichment effect of ion-supported magnetic nanomaterials is superior to the phosphopeptide enrichment effect of commercial Ti O₂ materials. When new materials were used for the actual sample Hela cell phosphopeptide enrichment and mass spectrometry identification, a single mass spectrometry analysis identified 9048 phosphorylated peptides corresponding to 2103 phosphorylated proteomes.