PSA-GUI: A Windows-Based Graphical User Interface for the Projected Superposition Approximation Collision Cross-Section Calculation.

The structural analysis of biological molecules from ion mobility/mass spectrometry (IM/MS) experiments requires the comparison of measured collision cross-sections with theoretical models. The key step for this purpose is the calculation of collision cross-section for the theoretical models. Multiple methodologies have been established, including the projected superposition approximation (PSA) method. In this study, we introduce PSA-GUI, a cross-platform scientific-software implementation of the established PSA method that uses the Windows Subsystem for Linux (WSL) to enable execution on Windows systems. PSA-GUI integrates PSA parameter control, automated PDB and XYZ file handling, multimodel conformer extraction, resource-aware batch execution, and real-time job monitoring into a workflow for individual structures and conformational ensembles, thereby facilitating its use in structural-biology applications.