Analytical Sciences

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

Hiroko SEKI,*^1,*² Yoshihisa SEI,*^1,*² Kazuaki SHIKII,*^1,*³ Sakurako SHIMOTAKAHARA,*⁴ Hiroaki UTSUMI,*⁵ Kentaro YAMAGUCHI,*^1,*² and Mitsuru TASHIRO*⁶

*1 Chemical Analysis Center, Chiba University, Yayoi, Inage, Chiba 263-8522, Japan
*2 CREST, Japan Science and Technology Agency (JST), Japan
*3 Analysis Research Department, Chemical Research Laboratories, Nissan Chemical Industries Ltd., Tsuboi, Funabashi, Chiba 274-8507, Japan
*4 School of Pharmacy, Tokyo University of Pharmacy and Life Science, Hachioji, Tokyo 192-0392, Japan
*5 NM Application & Research Group, Application & Research Center, Analytical Instruments Division, JEOL Ltd., Musashino, Akishima, Tokyo 196-8558, Japan
*6 Department of Chemistry, Faculty of Science, Tokyo Metropolitan University, Hachioji, Tokyo 192-0367, Japan

A difference diffusion-based NMR technique and cold-spray ionization mass spectrometry were employed as a solution-based approach for identifying a ligand binding with a protein receptor. The difference diffusion-based NMR technique, called difference NOE-pumping, can directly detect the ligand interacting with a protein receptor. This technique uses a simple pulse sequence and the diffusion filter can easily be optimized. The cold-spray ionization mass spectrometry (CSI-MS), a variant of electrospray ionization mass spectrometry (ESI-MS) operating at low temperature, has been applied to detect the ligand-receptor complex. The efficiency of these techniques for identifying binding ligands is demonstrated with the human serum albumin (HSA)-drug system.

J-STAGE: View this article in J-STAGE