Ultra-high performance liquid chromatography-mass spectrometry (UPLC-MS) is a high-throughput analytical technique that has been rapidly developed in the last decade or more. It is widely used in environmental science, medicine, and drug research and development, and is used to detect polar and medium-polar organic chemistry. The golden rule of things. However, this technology hides some flaws. For example, some compounds can undergo redox reactions on electrospray ionization sources (ESI); in addition, UPLC columns can generate strong shear forces that can break down macromolecular compounds such as polymers. Recently, under the guidance of Peng Xianzhi, a researcher of the Guangzhou Institute of Geochemistry at the Chinese Academy of Sciences, Dr. Tang Caiming and engineer Jianjian Tan of the Guangzhou Institute of Quality Supervision and Inspection conducted a study to find and confirm the oxidation reaction of reducing analytes on UPLC columns. (Figure 1), and successfully developed a method to solve this problem of oxidation on the column. The group unexpectedly discovered in a natural product analysis study that polyphenolic plant extracts may undergo oxidation reactions in the UPLC-MS system, resulting in reduced and unstable analyte signals, resulting in ineffective quantitative analysis. Qualitative analysis also has the risk of misjudgment. In this regard, the researchers used high-resolution mass spectrometry technology, combined with the post-column pumping the reducing agent solution and the analyte solution, to confirm that the oxidation-producing analytes such as polyphenols can be oxidized on the UPLC column, and the oxidation degree is significant ( figure 2). By analyzing the chromatograms, the investigators speculate that the site of the oxidation reaction should be the UPLC exit-end sieve plate, so a series of experiments was designed to verify this inference. Finally, the researchers solved the problem of oxidation on the UPLC column by pumping the reducing agent solution through the column, and thought that the principle may be that the reducing agent reacts with the oxidation product in the high temperature ESI and restores it to the original analyte form. (image 3). This research result is of great significance to natural product research and is expected to play an active role in drug analysis and protein analysis. The AQSIQ Public Welfare Fund provided partial funding for the study. Flashlight,Flashlight Rechargeable,LED Flashlight,USB Rechargeable Flashlight,Blaze Flashlight Yuyao Flylit Appliance Co.,Ltd , https://www.flylitlight.com