| 摘要 |
PROBLEM TO BE SOLVED: To produce positive or negative ions with high efficiency, by installing an electrode near a spray capillary and by applying an electric field on liquid and by spraying the liquid, in a sonic spray ionization method. SOLUTION: This ion source is equipped with a capillary 2 for spraying liquid into the atmospheric air, and an orifice 3 installed by inserting a part near the head of the capillary 2 and formed so that gas will flow up to the head of the capillary 2 along the circumferential wall surface of the capillary 2. A gas flow velocity near the head of the capillary 2 is about a sound velocity, and a voltage is applied between the liquid in the capillary 2 and the orifice 3 or an electrode installed near the capillary 2. Hereby, the electric potential of the liquid can be set equally to the earth potential, and combination of a solution separation means with a liquid introduction part is easily realized. Also, the polarity of produced ions can be controlled according to the polarity of the voltage applied on the electrode. Besides, multi-charged ions of material having a large mass, such as a protein or the like, or the like can be produced with high efficiency and excellent repeatability. |
