DEVELOPMENT OF A COMPUTATIONAL COLLISION CROSS SECTION DATABASE FOR SINGLY AND DOUBLY CHARGED POLYALANINE CATIONS

The critical role of PolyAlanine (PolyA) molecules as calibration standards in mobility measurements accentuates the importance of a universally applicable and comprehensive Collision Cross Section (CCS) database. This necessity is driven by the goal to eliminate experimental discrepancies due to lab-specific or instrument-specific conditions, and to strengthen the robustness of experimental outcomes. Using the POMICS workflow, I have advanced this research by performing a comprehensive analysis of CCS values for 〖(PolyA)〗_n^Z cations, where n indicates the number of alanine repeats ranging from 3 to 18, Z equals +1 and +2, in He and N2 as buffer gases. The findings closely match the experimentally derived values, showing an average error of 2.80 % and 3.10 % for CCS values of singly charged cations in He and N2, respectively, 3.88 % and 3.90 % for CCS values of doubly charged cations in the same gases. Through the creation of a robust CCS database for poly-alanine molecules, this study makes a significant contribution to enhancing precision in metabolomics research. This development will streamline metabolite identification and measurement across multiple laboratories and disciplines, further solidifying the foundation for future research aimed at creating a more encompassing CCS database for other mobility calibrants.