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Title: Mobilized Electrospray Device for On-Tissue Chemical Derivatization in MALDI-MS Imaging
Applying solutions of matrix or derivatization agent via microdroplets is a common sample preparation technique for matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI) experiments. Mobilized nebulizer sprayers are commonly used to create a homogeneous matrix or reagent layer across large surfaces. Electrospray devices have also been used to produce microdroplets for the same purpose but are rarely used for large tissues due to their immobility. Herein, we present a movable electrospray device that can be used for large tissue sample preparation by a simple modification to an automatic commercial nebulizer device. As demonstrated for on-tissue chemical derivatization (OTCD) with Girard's reagent T using a mimetic tissue model, the sprayer has the additional benefit of being able to investigate reaction acceleration in OTCD when comparing electrostatically charged spray to electrostatically neutral spray. Finally, MALDI-MSI of fatty alde-hydes is successfully demonstrated in rat brain tissues using this device for both OTCD and matrix application.  more » « less
Award ID(s):
1905335
PAR ID:
10525412
Author(s) / Creator(s):
; ;
Publisher / Repository:
American Chemical Society
Date Published:
Journal Name:
Journal of the American Society for Mass Spectrometry
Volume:
35
ISSN:
1044-0305
Page Range / eLocation ID:
205-213
Subject(s) / Keyword(s):
on-tissue chemical derivatization, electrospray, reaction acceleration, mass spectrometry imaging
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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