Direct characterization of solid phase resin-bound molecules by mass spectrometry

In this work we demonstrate that analytes, covalently linked to a polymeric support through a photolabile linker, can be directly analyzed by matrix-assisted laser desorption/ionization (MALDI). Mass spectral analysis is performed in a single step requiring no pretreatment of the sample to induce cleavage from the support. Our results show that the UV laser light in the MALDI experiment can be used to simultaneously promote an analyteʹs photolytic cleavage from a solid support and its gas phase ionization for subsequent mass spectral analysis. In this manner, MALDI facilitates the dissociation and identification of resin-bound analytes in a single analytical procedure without the need for any prior chemical treatment.