When using 1-pass routines, the cIM operates such that all ions pass through the mobility device only once, irrespective of their size and charge. However, owing to the device's longer 98 cm path length, 1-pass cIM still theoretically provides higher resolution mobility separations than its 25 cm linear counterpart . As expected, use of Cyclic IMS with 1-pass routine provided a substantial increase in peptide identification for all assessed targets (Figure ). When compared to the SYNAPT G2-Si instrument, 1-pass on the Cyclic IMS provided peptide identification increases of 144, 32, 48, and 24% for SMO, XylE, MsbA and SecYEG, respectively, which translated into increased sequence coverage and/or redundancy for all assessed targets (Figure and Table ). In the case of SMO, the increased peptide identification afforded by cIM 1-pass led to a 22% increase in sequence coverage, thereby permitting capture of sequence segments within functionally important regions (ICL2, TMD4, ECL2, TMD6 and ECL3) that were previously omitted during HDX-MS optimisation efforts on SYNAPT G2-Si instrument (Figure ). This demonstrates that use of next generation cIM instrumentation can increase the information content, and therefore value, of bottom-up LC-MS data when analysing challenging IMP targets such as GPCRs. For XylE, MsbA and SecYEG, less pronounced increases in sequence coverages were observed (Table ); likely a direct result of the coverage for these targets already being particularly high on SYNAPT G2-Si instrument. Nevertheless, the increased peptide identification afforded by cIM 1-pass also led to a 59, 10, 30, and 14% increase in redundancy for SMO, XylE, MsbA and SecYEG, respectively, thereby significantly increasing the spatial resolution of the data (Table ).