The chemical and structural heterogeneity of toxoid vaccines makes their analysis challenging. However, detailed insights on a molecular level can be obtained by mass spectrometry. Our initial... Show moreThe chemical and structural heterogeneity of toxoid vaccines makes their analysis challenging. However, detailed insights on a molecular level can be obtained by mass spectrometry. Our initial focus was the identification of formaldehyde-induced modifications in diphtheria toxin, which is described in Chapter 2. Subsequently, the methods described in Chapter 2 were applied to study what effects formaldehyde-induced modifications on model proteins have on their susceptibility to enzymatic proteolysis (Chapter 3). During the analysis of these model proteins, unknown formaldehyde-induced modifications were observed. The structural elucidation of these modifications, the discovery of a new type of crosslinks and various other subsequent reaction products are described in Chapter 4. The degradomics analysis described in Chapter 3 was applied to tetanus toxoids to distinguish heat-denaturated toxoids from their original state (Chapter 5). In order to reduce the analysis time and further improve the degradomics approach, an optimized strategy using Tandem Mass Tag multiplexing for the relative quantification of peptides was developed for the analysis of diphtheria toxoids (Chapter 6). Finally, Chapter 7 provides a brief discussion on the results presented in this thesis and offers some perspectives on implementation of the findings for toxoid vaccine development, quality control and further research. Show less
