RPLC-MS analysis of enriched integral membrane proteins from HEK293T cells. (a-f) Representative charge state distributions and deconvoluted mass spectra from SEC fraction 3. Proteins include sideroflexin-1 (SFXN1), transmembrane protein 33 (TMEM33), mitochondrial carrier homolog 2 (MTCH2), ADP ribosylation factor like GTPase 6 interacting protein 1 (ARL6IP1), ER lumen protein-retaining receptor 1 (KDELR1), and transmembrane protein 109 (TMEM109). (g) Base peak chromatography (BPC) demonstrating effective membrane protein separation using PLRP stationary phase. (h) Extracted ion chromatograms (EIC) were generated to further demonstrate their effective separation using PLRP material. The number of transmembrane domains (#TMD) ranged from 2–19. Peak heights are not representative of protein MS signal intensity. (i) GRAVY score of representative proteins (indicated by gene name) in order of elution. Proteins with lower scores generally eluted earlier while proteins with higher scores eluted later.