This review describes modern mass spectrometric techniques which make
it possible to apply to highly polar and large biomolecules. In recent
years, the use of mass spectrometry has dramatically expanded in bioc
hemical and medical fields. Significant developments in these techniqu
es have been established by ESI/MS (electrospray ionization mass spect
rometry) and MALDI-TOF/MS (matrix-assisted laser desorption ionization
time-of-flight mass spectremetry). ESI can detect weak interactions s
uch as cyclodextrin inclusion complexes, enzyme-substrate complexes, d
ouble stranded DNA and its intercalation with a ligand. It is expected
to be a powerful tool for study of molecular recognition at the picom
olar level. ESI can also be easily interfaced with liquid chromatograp
hy (LC/MS). On-line LC/MS is widely applicable for mixture analysis. M
ALDI-TOF provides extremely high sensitivity Such as sub picomolar lev
el analysis. PSD-MS (post source decay-mass spectrometry) gives struct
ural information, which is a technique similar to CID-MS/MS with extre
mely high sensitivity.