In positive-ion fast atom bombardment (FAB) mass spectrometry, it is difficult to determine the molecular weights of oligosaccharides due to the low abundance of [M+H]+ion. However, when oligosaccharides are mixed wit...In positive-ion fast atom bombardment (FAB) mass spectrometry, it is difficult to determine the molecular weights of oligosaccharides due to the low abundance of [M+H]+ion. However, when oligosaccharides are mixed with an appropriate amount of NaCI and LiCI, two highly abundant peaks[M+Na]+and [M+Li]+appear in FABmass spectra and their mass difference is 16. From the adduct ions, the molecular weights of oligosaccharides can be determined unambiguously. In the same way, when a mixture of oligosaccharides was mixed with an appropriate amount of Na+ and Li+, pairs of strong peaks appeared in the FAB mass spectra. These adduct ions were easily recognized due to the fact that they were very strong and their mass difference was union(16u). From these adduct ions, the molecular weight of each oligosaccharides in mixture may be determined.展开更多
It is reported ruthenium complexes show no photoluminescence in aqueous solution at ambient temperature, but display intense photoluminescence in The presence of double- helical DNA,to which The complex bind avoidly. ...It is reported ruthenium complexes show no photoluminescence in aqueous solution at ambient temperature, but display intense photoluminescence in The presence of double- helical DNA,to which The complex bind avoidly. These characteristics may become particularly useful in developing new diagnostic reagent based upon luminescent DNA probes. So, There has been increasing attention given to The design of ruthenium complexes and Their photoluminescence characteristics. But there is no report on mass spectromotric study of These complexes. In this paper, The fast atom bombardment mass spectra of newly synthesized ruthenium complex Ru（bpy）2（dppx） （BF4） 2 （bpy=2, 2’bipyridine, dppx=dipyrido<3,2, -a-2’, 3’-c>phenaxylene）was discussed. A ccording to The fragment ions and related knowledge, The molecule structure is characterized. These will provide some valuable references to synthesize These complexes and characterize Their molecule Structures.展开更多
文摘In positive-ion fast atom bombardment (FAB) mass spectrometry, it is difficult to determine the molecular weights of oligosaccharides due to the low abundance of [M+H]+ion. However, when oligosaccharides are mixed with an appropriate amount of NaCI and LiCI, two highly abundant peaks[M+Na]+and [M+Li]+appear in FABmass spectra and their mass difference is 16. From the adduct ions, the molecular weights of oligosaccharides can be determined unambiguously. In the same way, when a mixture of oligosaccharides was mixed with an appropriate amount of Na+ and Li+, pairs of strong peaks appeared in the FAB mass spectra. These adduct ions were easily recognized due to the fact that they were very strong and their mass difference was union(16u). From these adduct ions, the molecular weight of each oligosaccharides in mixture may be determined.
文摘It is reported ruthenium complexes show no photoluminescence in aqueous solution at ambient temperature, but display intense photoluminescence in The presence of double- helical DNA,to which The complex bind avoidly. These characteristics may become particularly useful in developing new diagnostic reagent based upon luminescent DNA probes. So, There has been increasing attention given to The design of ruthenium complexes and Their photoluminescence characteristics. But there is no report on mass spectromotric study of These complexes. In this paper, The fast atom bombardment mass spectra of newly synthesized ruthenium complex Ru（bpy）2（dppx） （BF4） 2 （bpy=2, 2’bipyridine, dppx=dipyrido<3,2, -a-2’, 3’-c>phenaxylene）was discussed. A ccording to The fragment ions and related knowledge, The molecule structure is characterized. These will provide some valuable references to synthesize These complexes and characterize Their molecule Structures.
