Phospholipids are amphiphilic molecules and key components of cell membranes. Due to their emulsifying and antioxidant properties, they are widely used in the pharmaceutical, food and cosmetics industries. Lecithin, a natural source of phospholipids, is mainly used in the food and cosmetics industry. The phospholipid composition of lecithin depends on its source and primarily influences its emulsifying properties. In my master thesis I developed a method to identify phospholipids in lecithin samples without using standards. I developed and optimised a method for the separation of phospholipids by HPLC and LC-MS using FullMS and MS-MS modes at a collision energy of 40 eV. I identified individual phospholipids by analysing the mass spectra. In a first step, I created a programme in Python that provided a set of possible phospholipids for each molecular ion. In the second step, I analysed the fragmentation ions in the mass spectrum according to the proposed fragmentation mechanism and qualified the phospholipids present in the lecithin sample. Finally, I confirmed with selected standards that the identification was correct.
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