Magnetic metal-organic framework nanocomposites for enrichment and direct detection of small molecules by negative-ion matrix-assisted laser desorption/ionization time-of-flight mass spectrometry

Zeolitic imidazolate framework-8 coated magnetic nanocomposites (Fe3O4@ZIF-8 MNCs) served as an absorbent and a matrix for negativeion MALDI-TOF MS. The host-guest property and interference-free background made them an ideal dual platform for the sensitive analysis of small molecules.