To provide an improved method for directly identifying the chemical structures of substances present in tissues or cells of organisms.
The method for directly identifying the chemical structures of substances present especially in tissues or cells of organisms of various kinds comprises (1) the step of applying a laser beam to a slice of sample tissue or a specific intracellular region of a cell and analyzing generated mass ions to obtain mass spectra of substances present in that portion; (2) the step of analyzing the mass spectra to obtain the mass profiles of the substances present in the slice of sample tissue or the intracellular region of the cell; and (3) the step of determining the chemical structures of the substances corresponding to specific molecular weights appearing in the mass profiles. The method is effected by use of techniques which use in combination a matrix assisted laser desorption ionization time-of-flight mass spectrometer(MALDI-TOF MS) and an on-line capillary opposite phase HPLC/quadrupole orthogonal acceleration time-of-flight(Q-Tof)-MS, and by use of molecular cloning.
YASUDA YOSHIMI
NAKAJIMA TERUMI
