Gold Nanoparticles for Enhanced Ionization and Fragmentation of Biomolecules using LDI-MS.

New applications for gold nanoparticles (AuNPs) in Laser Desorption Ionization Mass Spectrometry (LDI-MS) are presented here. This work expands on previous biomolecule studies and introduces carbohydrates, steroids, bile acids, and other small molecules as a focus. Broad trends in ionization are observed and specifically of interest are new species that have not previously been reported from AuNPs (e.g., [M+Au]+ ). Interesting fragmentation effects have been observed for diphenhydramine, including similarity to Electron Impact mass spectra and possible radical driven reactions, providing insight into the mechanism of ionization when using AuNPs.