Laser Desorption Ionization of Stilbenes in Crystalline Sponge

Abstract

The laser desorption (LD) ionization of three stilbenes in the nano porous metal-organic frameworks called "crystalline sponge" is demonstrated. The analyte position in the pore and the interaction between the analyte and the framework that functions as a matrix are discussed based on the results of single- crystal X-ray analysis. It is confirmed that the analyte/ligand ratio of 1:2 is sufficient for the analyte ionization. This method makes it possible to visualize hot spots on a target plate to be irradiated. That the sample requirement is dramatically reduced to the order of femtomoles is also an advantage. The relationship between laser interaction, analyte position in the pore, and analyte/ligand ratio is discussed as a new ionization field to elucidate the molecular structure of the analyte by LD ionization mass spectrometry.

Applications of the crystalline sponge method and developments of alternative crystalline sponges

“…Similarly, NMR studies contributed to the absolute structure determination of six more sesquiterpenes extracted from the same macroalga, 46 natural products such as collimonins A−D, 47 tenebrathin, 48 and fuliginone extracted from an australian plant. 49 Yamaguchi et al 50 introduced Laser Desorption Ionisation-Mass spectroscopy (LDI-MS) in combination with CSM (CS-LDI-MS) to explore the use of crystalline sponge 1 as a matrix to understand the ionisation mechanism of matrix-assisted laser desorption ionization (MALDI). The analyte encapsulated sponge 1 was ionised by laser desorption and analyte orientation in the pore, as well as interaction with the framework, was studied by CSM.…”

Application of Crystalline Matrices for the Structural Determination of Organic Molecules

“…While 1 has been extensively studied and applied, − it has its limitations. The maximum recommended guest size for 1 is 500 MW, and it is incompatible with very basic/nucleophilic moieties and with highly polar solvents that may be needed for sufficient target solubilization.…”

Combined Analysis Based on a Crystalline Sponge Method

“…The combined use of MS and the CS method was firstly reported in 2015. 21 Stilbene derivatives were encapsulated in CS nanopores, and one CS suitable for X-ray structure analysis was selected for collection of diffraction patterns for structure analysis. After diffraction measurement, a single crystal was subjected to LDI.…”