We separate different fragments in the sample using techniques such as high-performance liquid chromatography (HPLC) or ion exchange chromatography (IEC). Moreover, mass spectrometry (MS) and nuclear magnetic resonance (NMR) technology are combined to conduct qualitative and quantitative analysis of 3-O-sulfation in different fragments by detecting specific ions or ion fragments. In addition, we set up controlled experiments to verify the existence of 3-O-sulfation through multiple experiments and repeated testing.
