Methods and devices for performing matrix assisted laser desorption/ionization protocols

Methods and devices for performing matrix assisted laser desorption/ionization protocols are provided. In accordance with the subject methods, an analyte is first deposited into a fluid retaining structure (30) present on a substrate (31) surface. The fluid retaining structure (30) includes a material that changes from a first fluid state to a second solid state in response to an applied stimulus. The resultant retained analyte is then digested with an analyte-digesting reagent to produce fragments of the analyte. The resultant fragments are then ionized for subsequent mass spectrometry analysis. Also provided are devices, e.g., sample holders (33), suitable for use in the subject methods. Kits for use in the subject methods are also provided.