Extraction of Dissolved Organic Matter (DOM) from Central Seawater of Northern SCS and Unravelling StructuralComplexity of DOM, Particulate OM Using 13C & 1H NMR Spectroscopy & High-Resolution Mass Spectrometry (Orbitrap-MS)
Zhou Zhen-song 1, Wu Yi-xin 1, Wang Xiao-cong 2,1, Song Gui-xue 1,*, Zhang Yong 1,*
1. Institute of Marine Science and Technology, Shandong University, Qingdao, Shandong;
2. College of Science, China University of Petroleum (Beijing)
Dissolved organic matter (DOM) is a complex mixture with aromatic and aliphatic hydrocarbon structures and rich in various functional groups and elements. It plays a vital role in physical, chemical, and biological of global carbon cycle. 150 mg DOM solid sample was obtained from approximate 200L seawater in south China sea via PPL solid-phase extraction (SPE)method. A series of spectral analyses, nuclear magnetic resonance spectroscopy (NMR) and mass spectrometry (MS) were used to acquire DOM sample’s characteristic of its structures and functional groups. The 3D fluorescence spectrum demonstrates that PPL—DOM has significant fluorescent signal in A peak and M peak, showing that PPL tends to retain humus-like substance in DOM. The Fourier transform infrared absorption spectrum (FT-IR) indicates that PPL—DOM has a significant absorption peak at 1720cm−1, which is formed by stretching vibration of C=O in carboxyl group. In the Orbitrap MS mode, after screening and matching, 3101 confirmed molecular formulas are obtained.
Keywords：dissolved organic matter, PPL resin, mass spectrometry
