Modern analytical labs face growing demands, from helium shortages to strict regulatory requirements, that push older gas chromatography (GC) methods and instruments to their limits. Staying competitive requires two key strategies: method optimization for faster, more precise analysis, and method translation to adapt workflows to advanced instruments.
Three recent application notes from Agilent showcase these strategies in action. By refining methods for faster analysis and adapting them for use across different setups, labs in industries such as petrochemicals, pharmaceuticals, and flavor testing are tackling their most pressing challenges. This article highlights insights from these application notes, illustrating how advancements in GC systems and software are helping labs improve throughput, enhance quality control, and stay adaptable for the future.
Efficient Hydrocarbon Analysis with Dual Flow GC
Monocyclic aromatic hydrocarbons (MAHs) such as benzene, toluene, and xylene are critical building blocks for industries including petrochemicals, solvents, and plastics. Labs tasked with analyzing these compounds encounter obstacles, particularly when handling large sample volumes. For instance, ASTM D7504, a widely used method for MAH analysis, often requires extended runtimes and relies on helium as a carrier gas.
An Agilent study, detailed in The Analysis of Monocyclic Aromatic Hydrocarbons by ASTM D7504 on the Agilent 8850 GC System, illustrates how innovative instrumentation and workflow design enhance MAH analysis.
Using the Agilent 8850 GC, a compact instrument with dual gas flow capabilities, researchers compared two workflows under ASTM D7504 standards. The conventional method relied on helium as the carrier gas and a 60-meter polyethylene glycol column, achieving precise separation of benzene, toluene, and xylene isomers over a 39-minute runtime.
Researchers optimized the method by using a shorter, narrower 10-meter column, which reduced elution time by minimizing compound travel distance. Hydrogen, with its higher diffusivity compared to helium, further accelerated separation while maintaining baseline resolution for critical peaks such as ethylbenzene and xylene isomers.
Oven temperature programming was adjusted with a steeper ramp to speed up elution without compromising separation, and column flow rates were fine-tuned to align with hydrogen’s properties. These adjustments were guided by Agilent’s Method Translation Software, which ensured the optimized workflow adhered to ASTM D7504 requirements while maintaining precision.
The result was a faster, highly reproducible method, with RSD values below 1.0 percent for all major analytes—demonstrating how targeted changes to key parameters can significantly enhance throughput while meeting industry standards.
Optimized GC Workflows for Residual Solvent Testing
Residual solvents are volatile chemicals used during the production of active pharmaceutical ingredients (APIs) and excipients. To ensure safety, these compounds must be monitored in accordance with USP <467>, which sets toxicity-based limits for solvent residues. In pharmaceutical labs, headspace gas chromatography (GC) is a preferred technique for this analysis, as it heats samples to release vapor-phase compounds, enabling precise detection and quantitation.
While effective, traditional headspace GC workflows for USP <467> compliance often rely on helium as the carrier gas, a resource facing rising costs and supply constraints. Additionally, the lengthy runtimes required to achieve precise separation can limit throughput, creating bottlenecks in high-demand labs. For facilities with limited bench space, the size of conventional GC systems adds another layer of complexity, making it difficult to scale operations efficiently.
In the application note Residual Solvents Analysis for the Pharmaceutical Industry Using the Agilent 8697 Headspace Sampler and 8850 GC-FID System, researchers from Agilent demonstrate how the integration of modern GC tools can reduce analysis time by up to 30% while maintaining precision in detecting residual solvent impurities required for regulatory compliance.
To ensure reproducibility in high-throughput testing, researchers used the Agilent 8697 Headspace Sampler’s automated vial handling to minimize variability in sample introduction. Paired with the compact 8850 GC system, they first tested a helium-based workflow modeled on the traditional USP <467> method. While this approach delivered precise separations for residual solvents, it required runtimes of over 40 minutes per analysis.
To enhance efficiency, researchers switched from helium to hydrogen as the carrier gas and optimized method parameters using Agilent’s Method Translation Software to account for hydrogen’s properties. Challenging separations, such as methylene chloride and acetonitrile—compounds with high volatility and closely overlapping retention times—required precise adjustments. These modifications reduced analysis time significantly while preserving resolution.
With RSD values below 1.0 percent, the approach ensures reliable results even for challenging separations, making it ideal for high-throughput pharmaceutical labs.
Fast and Precise Flavor Analysis
In the food and beverage industry, flavor profiling is crucial for ensuring product quality and consumer satisfaction. For instance, the distinctive flavor of vanilla extract comes from a complex mix of volatile organic compounds (VOCs) that require precise GC separation to identify key components such as vanillin. Traditional GC methods, however, are often time-consuming, limiting efficiency in high-throughput production environments.
An Agilent study, Method Translation for the Analysis of Vanilla Extracts Using an Agilent 8850 GC System with Helium Conservation Module for Carrier Gas Switching, showcases an approach to balancing speed and precision in the analysis of challenging flavor profiles.
Researchers began by evaluating a traditional GC method for analyzing vanilla extract, which used helium as the carrier gas and required runtimes of up to 50 minutes to separate the complex mix of VOCs. Using the Agilent 8850 GC system, they transitioned to hydrogen as the carrier gas and employed shorter, narrower columns to achieve faster separations. Agilent’s Method Translation Software guided adjustments to flow rates and oven temperature programming, ensuring the new workflow maintained accuracy while reducing runtimes to under 15 minutes.
This fast method addresses the high-throughput needs of QC labs in flavor manufacturing, where rapid raw ingredient purity analysis is essential. By utilizing shorter, smaller diameter columns and hydrogen as a carrier gas, the optimized approach achieved a 14-fold speed improvement over traditional helium-based workflows.
Researchers used the helium conservation module to enable seamless gas switching during high-throughput operations, transitioning between helium and hydrogen within a single sequence without disrupting workflows or requiring manual adjustments. This approach maintained less than 2.5% variability and delivered precise, reliable quantitation, making it ideal for flavor analysis in both R&D and QC environments.
Conclusion
Method optimization and translation connect legacy workflows with modern GC systems, retaining institutional knowledge while enhancing analytical capabilities. This strategy allows labs to modernize incrementally, balancing proven methods with cutting-edge performance to build future-ready systems.
Adam Dickie is a science writer at Separation Science. He can be reached at adickie@sepscience.com.
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This article is featured in our March 2025 publication, Redefining Analytical Boundaries. Explore this issue to unlock AI-driven efficiency, advanced mass spectrometry insights, and sustainable chromatography breakthroughs.
