ja8b02918_si_001.pdf (1.39 MB)
Traceless Immobilization of Analytes for High-Throughput Experiments with SAMDI Mass Spectrometry
journal contribution
posted on 2018-06-14, 00:00 authored by Kazi Y. Helal, Azmain Alamgir, Eric J. Berns, Milan MrksichLabel-free assays, and particularly
those based on the combination
of mass spectroscopy with surface chemistries, enable high-throughput
experiments of a broad range of reactions. However, these methods
can still require the incorporation of functional groups that allow
immobilization of reactants and products to surfaces prior to analysis.
In this paper, we report a traceless method for attaching molecules
to a self-assembled monolayer for matrix-assisted laser desorption
and ionization (SAMDI) mass spectrometry. This method uses monolayers
that are functionalized with a 3-trifluoromethyl-3-phenyl-diazirine
group that liberates nitrogen when irradiated and gives a carbene
that inserts into a wide range of bonds to covalently immobilize molecules.
Analysis of the monolayer with SAMDI then reveals peaks for each of
the adducts formed from molecules in the sample. This method is applied
to characterize a P450 drug metabolizing enzyme and to monitor a Suzuki–Miyaura
coupling chemical reaction and is important because modification of
the substrates with a functional group would alter their activities.
This method will be important for high-throughput experiments in many
areas, including reaction discovery and optimization.