PMID- 32840500 OWN - NLM STAT- MEDLINE VI - 145 IP - 21 TI - Multimodal imaging of biological tissues using combined MALDI and NAPA-LDI mass spectrometry for enhanced molecular coverage. PG - 6910-6918 LA - eng PT - Journal Article PL - England TA - Analyst JT - The Analyst JID - 0372652 IS - 1364-5528 (Electronic) LID - 10.1039/d0an00836b [doi] FAU - Fincher, Jarod A AU - Fincher JA AD - Department of Chemistry, The George Washington University, Washington, DC 20052, USA. vertes@gwu.edu andrew.r.korte@gmail.com. FAU - Korte, Andrew R AU - Korte AR FAU - Yadavilli, Sridevi AU - Yadavilli S FAU - Morris, Nicholas J AU - Morris NJ FAU - Vertes, Akos AU - Vertes A IS - 0003-2654 (Linking) RN - Z4152N8IUI (Silicon) SB - IM MH - Animals MH - Lasers MH - Mice MH - *Molecular Imaging MH - Multimodal Imaging MH - *Silicon MH - Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization DCOM- 20210514 LR - 20210514 DP - 2020 Oct 26 AB - Mass spectrometry imaging (MSI) is a powerful analytical technique that enables detection, discovery, and identification of multiple classes of biomolecules, while simultaneously mapping their spatial distributions within a sample (e.g., a section of biological tissue). The limitation in molecular coverage afforded by any single MSI platform has led to the development of multimodal approaches that incorporate two or more techniques to obtain greater chemical information. Matrix-assisted laser desorption ionization (MALDI) is a preeminent ionization technique for MSI applications because the wide range of available matrices allows some degree of enhancement with respect to the detection of particular molecular classes. Nonetheless, MALDI has a limited ability to detect and image several classes of molecules, e.g., neutral lipids, in complex samples. Laser desorption ionization from silicon nanopost arrays (NAPA-LDI or NAPA) has been shown to offer complementary coverage with respect to MALDI by providing improved detection of neutral lipids and some small metabolites. Here, we present a multimodal imaging method in which a single tissue section is consecutively imaged at low and high laser fluences, generating spectra that are characteristic of MALDI and NAPA ionization, respectively. The method is demonstrated to map the distributions of species amenable to detection by MALDI (e.g., phospholipids and intermediate-mass metabolites) and NAPA (e.g., neutral lipids such as triglycerides and hexosylceramides, and small metabolites) in mouse brain and lung tissue sections.