The observation of non-covalent interactions in solution by electrospray ionization mass spectrometry: Promise, pitfalls and prognosis

On the specificity of cyclodextrin complexes detected by electrospray mass spectrometry

“…It has been suggested that lowering the sample concentration and the electrospray flow rate helps to prevent such nonspecific aggregation [1,4]. We therefore lowered the concentration close to the electrospray detection limit (4 ϫ 10 Ϫ5 M) for 1,10-da complexes with ␣-CD and maltohexaose complexes.…”

“…The contribution of the specific complex to the total signal intensity is found to increase with the diacid chain length, which is in agreement with solution behavior. (J Am Soc Mass Spectrom 2002, 13, 946 -953) © 2002 American Society for Mass Spectrometry F or the last ten years, electrospray mass spectrometry (ES-MS) has been used to investigate noncovalent complexes of different classes of compounds [1][2][3][4][5][6]. Electrospray mass spectrometry can be used basically in two different ways, each giving access to a different kind of information.…”

Stalking metal-linked dimers

“…Since then, ESI-MS has been used to detect a multitude of other protein dimers [40][41][42], including the oxygenase domain of nitric oxide synthase [43]. Although the ionization process involves the transfer of a protein from an aqueous to a gaseous phase, some dimeric species are able to survive the process [44][45][46]. Because the near absence of solvent upon transfer to the gas phase weakens hydrophobic interactions, ESI-MS is not a suitable method to determine the stability or the specific binding energy of protein dimers [47].…”

Application of Difference NOE-pumping NMR Technique and Cold-Spray Ionization Mass Spectrometry to Identify a Ligand Binding with a Protein Receptor

“…14,15 It facilitates observation of weaker associations among proteins, since the temperature at the spray interface is much lower. Although ESI-MS has been used for the detection of non-covalent macromolecular associations, [16][17][18][19] it is shown that CSI-MS is more sensitive in observations of macromolecular interaction. CSI-MS was successfully used to observe hyper-stranded DNA molecules that were unable to be detected by the ESI method 20 indicating the significant advance to detect non-covalent complexes in the biological systems.…”

“…Although ESI-MS has been used for the detection of non-covalent macromolecular associations, [16][17][18][19] it is shown that CSI-MS is more sensitive in observations of macromolecular interaction. CSI-MS was successfully used to observe hyper-stranded DNA molecules that were unable to be detected by the ESI method 20 indicating the significant advance Pharmacy and Life Science, Hachioji, Japan *5 NM Application & Research Group, Application & Research Center, Analytical Instruments Division, JEOL Ltd., Musashino, Akishima, Japan *6 Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Hachioji, Japan A difference diffusion-based NMR technique and cold-spray ionization mass spectrometry were employed as a solutionbased approach for identifying a ligand binding with a protein receptor.…”