Performance Benchmarking for Thermal Modulators in Comprehensive Two-Dimensional Gas Chromatography: Evaluation of the Solid-State Modulator

The recently introduced solid-state modulator (SSM) is a compact and relatively simple all-in-one solution to thermal modulation for use in comprehensive two-dimensional gas chromatography (GC×GC). In this work, we assess the performance of this modulator through a detailed assessment of its temperature stability and temperature programming capabilities, and corresponding retention time reproducibility. Through replicate analysis, 2D retention time standard deviation was determined to be 0.014 s (ranging from 0.000–0.023 s), corresponding to less than a single acquisition datapoint. Additionally, 1D retention time repeatability in GC×GC was assessed using a ‘super-resolution method’ designed to predict 1D retention based on the modulated peak distribution, and was determined to be comparable to that of conventional GC-MS analysis. A benchmarking framework was developed, which can be applied to future performance evaluations of thermal and other modulators, allowing for a more systematic comparison of modulation strategies.