Ion mobility spectrometry (IMS) is a rapidly trending separation strategy within the analytical community due to the complementary separation provided on a timescale conducive to existing LC- and imaging-MS based workflows. New IMS platforms often exhibit enhanced resolving power (Rp) in comparison to existing systems, and while additional separation capacity is always advantageous, ensuring these instrumental developments coincide with appropriate data extraction and analysis methods is pertinent to ensure routine adoption. Here we assess the performance of a new IMS-MS platform, the MOBILion MOBIE (v. 2.0), in relation to a commercially available drift tube platform, the Agilent 6560. Both instruments were operated using matched conditions where possible and metrics of scan speed, Rp, limits of detection (LOD), and propensity for isomer separations via LC-IMS-MS were evaluated. Results from this work indicate that both instruments operate with similar scan speeds in terms of IMS-MS frame generation, and CCS values calculated using the MOBIE were generally ≤1% difference in CCS relative to previously measured drift tube values. Skyline’s “Create Ion Mobility Library” feature was used to facilitate mobility integration despite this discrepancy, and both platforms were able to generate quantitative data using this method as demonstrated with a PFAS analysis of cell media and lysates and featured comparable LODs. The MOBIE system possesses much higher Rp in comparison to the 6560 (200-300 vs. 45-60 CCS/ΔCCS, respectively) and this advancement is clearly defined when assessing PFAS isomers and indicates great promise towards future applications of in-depth feature finding and biomarker discovery.

In this work we describe a unique approach for data acquired with MOBILion’s MOBIE system to help streamline data processing with existing analysis methods performed in Skyline. These results are compared with near-identical experiments conducted using a conventional DTIMS platform, the Agilent 6560, to assess the unique intricacies of enhanced mobility resolving power and its impact on data acquisition and quality.

Per- and polyfluoroalkyl substances (PFAS) are a class of industrially synthesized fluorochemicals designed as durable surfactants for use in a variety of household and industrial applications. Among their various uses, PFAS are typically acidic in their structural makeup and generally ionize well in negative ion mode. For this assessment of instrument performance, a commercially available reference standard PFAS mixture, EPA-533PAR (Wellington Labs, Guelph, Ontario) was utilized for mobility performance characterization and evaluation of limits of detection (LOD). To highlight the utility of both platforms for quantitative analysis of exposomic mixtures, cellular media and lysates spiked with PFAS were extracted and analyzed along with calibration curves established using serial dilutions of EPA-533 alongside a corresponding 13C labeled PFAS mixture also procured from Wellington Labs, MPFAC-C-ES. Mobile phase solvents and buffer salt (ammonium acetate) were purchased from Fisher Scientific (Hampton, NH) with Optima LC-MS grade purity.