No abstract

An effective La-complex-based probe ionization method is reported. Novel stable isotopically labeled probes containing the (15)N-labeled 2,6-bis(oxazolin-2-yl)pyridine (pybox) ligand, succinimide-tetramethylpybox (NHS-TMpybox), maleimide-tetramethylpybox (Mal-TMpybox), and 4-(tetramethylpybox)-butyl bromoacetate (BrAc-TMpybox), have been synthesized and their value in analyzing large complex molecules has been studied. The value of the (15)N-labeled pybox-La complex in ionizing various compounds, including bioactive peptides by cold-spray ionization mass spectrometry is emphasized.

We have developed a new ionization method that uses metal-complex-based ionization probes containing the 2,6-bis oxazolinyl pyridine pybox ligand, NHS-TMpybox, Mal-TMpybox, BrAc-TMpybox, oxime-TMpybox, and Sar-TMpybox. NHSTMpybox, Mal-TMpybox, BrAc-TMpybox, and oxime-TMpybox were reacted selectively with the functional groups of biomolecules, whereas Sar-TMpybox was reacted with carbon clusters.ese were able to obtain multiply charged ions of target molecules.is method was proven to e ectively ionize large complex molecules, including biomolecules and various supramolecules, as well as carbon clusters, such as fullerenes. Moreover, isotope-labeled pybox-La complexes were used to clearly detect isotopic labeling shi s.eir applications to multiply charged ionization, including isotope labeling of biomolecules and carbon clusters using cold-spray ionization mass spectrometry CSI-MS , are shown.