A MALDI plate suitable for MS or MS-MS analysis provided with a composite coating
that comprises a hydrophobic coating and a thin layer coating of a mixture of a
MALDI matrix material and an intercalating agent such as a polymer is disclosed.
A MALDI plate produced in accordance with the present teachings is useful for suppression
of matrix ions in the low mass region (1,000 daltons) of a MALDI-MS spectrum.