Silver nanoparticles on zeolite surface for laser desorption/ionization mass spectrometry of low molecular weight compounds

Silver nanoparticles loaded on NH 4 + -type zeolite, AgNPs–NH4ZSM5, was developed as an inorganic matrix for laser desorption/ionization mass spectrometry of low molecular weight compounds. It was found that AgNPs–NH4ZSM5 could work as an efficient Ag+ donor to ionize analytes and that zeolite worked as a heat bath to prevent the destruction of AgNPs after the photoexcitation. The AgNPs–NH4ZSM5 was applied to laser desorption/ionization mass spectrometry of biologically active substances with low molecular weights including acetylsalicylic acid, l-histidine, glucose, urea, cholesterol, and those in human serum.