Abstract:The rapid detection of pathogenic bacteria has become a topic spot.In the study，Fe3O4-COOH@MIL-101 nanoparticles were synthesized to improve the sensitivity and detection limit of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF MS/MS）to ribosomal proteins using its charged property and mesoporous enrichment ability.The conservation of ribosomal proteins had been used to identify E.coli O157∶H7.