Gas Chromatography Detector VGA-100 / VGA-101

Importance of the topic

Gas chromatography with vacuum ultraviolet (VUV) detection offers a universal, mass-sensitive approach to fuel and petrochemical analysis, overcoming limitations of traditional detectors by delivering both qualitative and quantitative spectral information in the 120–430 nm range. This capability is critical for resolving structural isomers, detecting trace compounds, and ensuring compliance with regulatory standards in quality control and research environments.

Objectives and overview

The main goal is to present the performance and versatility of the VGA-100/101 VUV detectors when coupled to a GC platform. Key objectives include demonstration of full-spectrum absorbance measurement, multi-method operation under official ASTM standards, automated deconvolution of co-eluting peaks, and rapid quantitation without extensive calibration procedures.

Methodology and Instrumentation

The VUV detector comprises a deuterium lamp, a 10 cm pathlength low-volume flow cell, diffraction grating optics and a detector array. The VGA-100 covers 120–240 nm, while the VGA-101 extends measurement to 430 nm and supports cell temperatures up to 430 °C. Integration with a GC inlet and oven allows carrier gases (H₂, N₂, He) and makeup gases (Ar, He, N₂) to purge background absorption. Data acquisition at >75 Hz captures three-dimensional chromatographic, absorbance and wavelength information. Software tools include VUVision for instrument control and data acquisition, and VUV Analyze for automated spectral deconvolution and reporting.

Main results and discussion

• Fuel identification performance is enhanced by full VUV spectral libraries covering paraffins, naphthenes, aromatics, olefins and oxygenates, enabling unambiguous compound classification and isomer discrimination.
• Time Interval Deconvolution (TID) slices co-eluting regions into regular time bins and resolves overlapping spectra, delivering reliable quantitation without pre-defined peak tables.
• PIONA analysis of reformulated gasoline (ASTM D8071) achieves class-based mass and volume percentages for paraffins, isoparaffins, naphthenes and aromatics in a single run.
• Jet fuel aromatics and saturates quantitation (ASTM D8267) is completed in 14 minutes without calibration curves, providing mono- and diaromatic content with clear chromatogram overlays.
• Diesel fuel analysis (ASTM D8368) simultaneously quantifies total aromatics, polyaromatic hydrocarbons (PAHs) and fatty acid methyl esters (FAMEs) in a single injection, supporting environmental and quality control needs.
• The VGA-101 expands the scope to high-boiling components, delivering extended wavelength data for heavy hydrocarbons and enhancing sensitivity via targeted spectral filters.

Benefits and practical applications

• Universal detection response for nearly all gas-phase molecules.
• Calibration-free quantitation reduces method development time.
• Compliance with multiple ASTM and EN fuel analysis standards on one platform.
• Automated, push-button data processing minimizes operator error.
• High-resolution spectral libraries support rapid unknown identification.
• Flexible expansion of user-defined libraries for specialized applications.

Future trends and opportunities

Emerging directions include coupling VUV detection with advanced multidimensional separations, integration with chemometric and machine learning algorithms for real-time spectral interpretation, application to environmental pollutants and complex biofuels, and further expansion of high-temperature detectors to characterize heavier hydrocarbon fractions and pyrolysis products.

Conclusion

Vacuum ultraviolet detection in gas chromatography represents a transformative tool for analytical chemistry, delivering universal absorbance data, precise isomer discrimination, and streamlined workflows across a broad range of fuel and petrochemical analyses. Its multi-method capability and automated spectral deconvolution position it as a versatile solution for both routine quality control and advanced research applications.

Used Instrumentation

• VUV Analytics VGA-100 Vacuum Ultraviolet Detector (120–240 nm)
• VUV Analytics VGA-101 Vacuum Ultraviolet Detector (120–430 nm, high-temperature cell)
• Shimadzu Nexis GC-2030 Gas Chromatograph
• Deuterium lamp light source and 10 cm pathlength flow cell
• VUVision software for data acquisition and instrument control
• VUV Analyze software for automated deconvolution and reporting
• Carrier gases: hydrogen, nitrogen, helium; Makeup gases: argon, helium, nitrogen