Mass spectrometer and spectrometry, which use near infrared fluorescence

A mass spectrometer using near infrared (NIR) fluorescence for combination of NIR fluorescence imaging and matrix assistant laser desorption/ionization (MALDI) imaging, comprising:

• a plate on which a sample is loaded, wherein the sample includes a fluorescent material having an excitation wavelength of an NIR wavelength band and a matrix for ionization, the sample comprising human tissue or animal tissue and a thickness of at least 10 μm;
• a fluorescence detection unit comprising a light source that irradiates the sample on the plate with excitation light to excite the fluorescent material included in the sample, the fluorescence detection unit acquiring a fluorescence image from a first surface of the plate responsive to the irradiation of the sample on the plate with the excitation light;
• a light emission unit configured to emit a laser beam for ionization at the sample on the plate, the laser beam emitted to a second surface of the plate that is opposite to the first surface of the plate;
• a moveable stage on which the plate is mounted, the moveable stage configured to move with respect to the fluorescence detection unit and the laser beam;
• and
• an ion detection unit configured to acquire a mass image of the sample by detecting ions generated from the sample due to the laser beam being emitted to the sample while moving the plate with respect to the laser beam using the moving stage,
• wherein the fluorescence detection unit and the ion detection unit are on a same axis but located opposite to each other with the plate between the fluorescence detection unit and the ion detection unit.