Sample preparation using MALDI mass
Corticosteroids as budesonide can be effective in reducing topic inflammation processes in different organs.
Therapeutic use of budesonide in respiratory diseases, like asthma, chronic obstructive pulmonary disease, and allergic rhinitis is well known.
However, the pulmonary distribution of budesonide is not well understood, due to the difficulties in tracing the molecule in samples.
In this paper, we present a matrix-assisted laser desorption/ionization mass spectrometry imaging protocol.
It can be used to visualize the pulmonary distribution of budesonide administered to a surfactant-depleted adult rabbit.
Considering that budesonide is not easily ionized by MALDI, we developed an on-tissue derivatization method with Girard's reagent P followed by ferulic acid deposition as MALDI matrix.
Interestingly, this sample preparation protocol results as a very effective strategy to raise the sensitivity towards not only budesonide but also other corticosteroids, allowing us to track its distribution and quantify the drug inside lung samples.