Accessible high-performance GC×GC: A DIY flow modulator with transient pulse sampling strategy.

Comprehensive two-dimensional gas chromatography (GC × GC) offers high separation capabilities for complex samples, but widespread adoption remains limited by instrumental costs. We present an integrated solution combining a cost-effective DIY flow modulator (main components <100 USD) with a transient pulse sampling (TPS) strategy. The TPS approach achieves superior separation efficiency through ultrashort sampling pulses (∼10 ms) while maintaining stable quantitative performance across diverse compound classes. Analysis of gasoline samples demonstrated accurate determination of benzene derivatives, oxygenates, and unconventional additives, with all results falling within the reproducibility tolerance specified by standard methods. The recovery rates for alcohols and unconventional additives ranged from 93.97 % to 109.3 %. Furthermore, cross-platform validation across three laboratories using four retrofitted 1D GC systems confirmed separation reproducibility, with inter-platform RSDs for aniline compounds ranging from 0.74 % to 2.77 % for trace additive analysis. The combination of cost-effective design, robust instrumentation, and validated quantitative performance makes this TPS-based modulation approach a practical solution for implementing GC × GC in both routine analysis and advanced research applications.