Dual-Column Analysis of Blood AlcoholContent (BAC) Using Nitrogen Carrier Gas with Brevis GC-2050

Importance of the Topic

Analysis of blood alcohol content and volatile organic compounds is critical for forensic and clinical applications. It supports law enforcement investigations, traffic safety, and medical diagnostics by providing accurate and reliable quantification of ethanol and related compounds in biological samples.

Objectives and Study Overview

This study aims to demonstrate dual-column headspace GC analysis of BAC using Shimadzu Brevis GC-2050 with nitrogen carrier gas. Key goals include cross-checking results via two columns, maintaining separation performance with a cost-effective gas, and validating method linearity, repeatability, and throughput.

Methodology and Instrumentation

Dual columns SH-BAC PLUS1 and SH-BAC PLUS2 were connected via a 2-hole ferrule to a dual-FID GC system coupled to an HS-20 NX headspace sampler. A compact Brevis GC-2050 was operated with linear velocity control at 30 cm/sec using nitrogen as carrier. The headspace oven was set at 65 °C, with the transfer line at 100 °C. Samples comprised 0.5 mL injected loops, standard solutions spiked into water or blood vials, and tert-butanol as internal standard. Consumables included restrictor tubing, union kits, and specialized ferrules.

Main Results and Discussion

Calibration curves for ethanol prepared in water and blood showed excellent linearity with R2 > 0.999 across 0.1 to 2.0 mg/mL. Repeatability of peak area ratios was within 2% RSD for both calibration matrices. Ten blood VOCs were fully resolved within 6 min on SH-BAC PLUS1 and 3.5 min on SH-BAC PLUS2. Retention time RSDs were below 1.6%. Preconditioning with high-concentration samples improved stability by saturating adsorption sites.

Benefits and Practical Applications

• Dual-column configuration enables cross-verification in a single run, improving qualitative confidence.
• Use of nitrogen reduces operating costs while preserving separation efficiency.
• Compact footprint of Brevis GC-2050 saves laboratory space and supports high throughput forensic screening.

Future Trends and Potential Applications

• Integration with mass spectrometry for enhanced compound identification.
• Real-time monitoring and field-deployable GC systems for roadside or onsite testing.
• Expansion of analyte panels to include emerging volatile biomarkers beyond alcohol.
• Automation and data processing using advanced software and AI tools for QC and regulatory compliance.

Conclusion

The dual-column HS-GC method using Brevis GC-2050 with nitrogen carrier gas delivers robust, cost-effective BAC analysis with excellent linearity, repeatability, and rapid separation of blood VOCs. This approach supports forensic, clinical, and safety applications requiring reliable alcohol quantification.

References

1. Shimadzu Application News 01-00899-EN First Edition June 2025