1D-O1-1525(1P-09) PDF
High-sensitive Analysis of Distribution of Phytochemicals by Using Imaging Mass Microscope
High-resolution spatial distribution of bioactive phytochemicals is indispensable information for elucidating their biological or pharmacological mechanisms, including bioavailability and biotransformation. However, this methodology still remains unclear due to the absence of an analytical technique easily detecting the naïve molecular localization in mammalian tissues. Recently, we succeeded in developing a novel technique of an in situ label-free imaging for visualizing the biotransformation of a representative green tea polyphenol. In this study, we attempted to develop highly sensitive matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) technique for visualizing distribution of phytochemicals. A deprotonated ion image and peak of strictinin, ellagitannin in green tea, or quercetin, vegetable flavonoid, within kidney sections after oral dosing was obtained by a mass microscope, iMScope TRIO (Shimadzu Corporation), using a naphthalene derivative as a matrix. Furthermore, unlike spray coating method using an airbrush, sublimation method using iMLayer (Shimadzu Corporation) also enabled to visualize distribution of phase II metabolites of quercetin. These results suggest that our proposed MALDI-MS techniques, using iMScope TRIO and iMLayer, may become a useful approach for sensitively visualizing distribution of phytochemicals within tissue micro-regions after oral dosing.