Application of Iron Oxide Nanoparticles in the Surface-Assisted Laser Desorption and Ionization-Mass Spectrometry of Small-Molecule Compounds

Iron oxide nanoparticles were applied to the surface-assisted laser desorption and ionization-mass spec-trometry (SALDI-MS) of small-molecule compounds, such as oligosaccharides, phytohormones, flavonoids, triglycerides, phospholipids, and amino acids. The spatial distribution of small-molecule compounds in soybean was further studied by using imaging mass spectrometry. After different preparation methods were compared, iron oxide nanoparticles calcined at 300 degrees C were selected. Results showed that in SALDI-MS analysis, iron oxide nanoparticles were characterized by good stability and low background noise. Analysis was performed in the positive ion mode at the laser energy of 70% with the average spectrum accumulated 30 times. The results showed that iron oxide nanoparticles had good repeatability and sensitivity in the analysis of the above -mentioned small-molecule compounds. Four samples, namely, sucrose, abscisic acid, DL-aspartic acid, and 1,2-dipalmitoyl-sn-glycerol-3-phosphorylcholine, were analyzed via SALDI-MS. The spot-to-spot repeatability IP: 203.8.109.20 On: Tue, 21 Mar 2023 09:07:49 RSD was less than 2.8%, and the interpoint repeatability RSD was less than 5.2%. The linear correlation coef-Copyright: American Scientific Publishers ficient of the four samples was R2 > 0.993 withn the concentration range of 0.05-1.0 mg/mL. On the basis Delivered by Ingenta of these results, the distribution of small-molecule components in soybean cotyledon, radicle, and germ was analyzed through SALDI-MSI.