MALDI电离原理Sample plate hn Laser1. Sample (A) is mixed with excess matrix (M) and dried on a MALDI plate. 2. Laser flash ionizes matrix molecules. 3. Sample molecules are ionized by proton transfer from matrix: MH++ AÆ M+ AH+.

AH+

+20 kV

Variable Ground Grid Grid

选择合适基质Sinapinic Acid a-Cyano-4-Hydroxycinnamic acid(CHCA) 2,5 Dihydroxybenzoic acid“Super DHB” 3-Hydroxypicolinic acid HABA蛋白质>10kDa多肽<10kDa Neutral Carbohydrates, Synthetic Polymers Proteins, Glycosylated proteins Oligonucleotides Proteins, Oligosaccharides

质量分析器

Q (quadrupole) 四极杆TRAP (Ion Trap) 离子阱TOF (Time -of –flight) 飞行时间FT (Fourier Transform) 傅立叶变换………