Matrix-Assisted Laser DesorpWon/IonizaWon Mass Spectrometry Imaging (MALDI MSI) is a robust technique that allows for mapping the distribuWon of molecules in the Wssue slices . This technique requires applicaWon of matrix on the analysed surface to allow for desorpWon/ionizaWon process following with ions transfer to a detector. MALDI is usually used for analysis of the large molecules (e.g. lipids, proteins) but someWmes, meeWng a few requirements, it is possible to measure small molecules either. There are special MALDI matrices that facilitate the measurements of certain molecules, but for some of them derivaWsaWon process is necessary. Our study was devoted to glucose analysis since its pivotal role in the biochemistry of the organism.