How Multidimensional Chromatography Depends on Nitrogen Generation

Background: Building a Cutting-Edge Analytical Lab

Dr. Petr Vozka established the Complex Chemical Composition Analysis Lab (C³AL) at California State University, Los Angeles (Cal State LA) with a mission to apply advanced analytical chemistry to real-world problems, particularly in forensic science. The lab focuses on comprehensive two-dimensional gas chromatography (GCxGC) to analyze complex mixtures, such as those found in fingerprint residues, fuels, and environmental samples. This state-of-the-art facility not only advances research but also provides hands-on training for undergraduate and graduate students, many from underrepresented backgrounds.

The Forensic Challenge: Fingerprint Aging Models

A key project at C³AL involves developing models to estimate the age of fingerprints using chemical analysis. This requires highly sensitive and reproducible measurements of both volatile and non-volatile compounds present in fingerprint residues. The workflow mirrors real-world forensic protocols: fingerprints are deposited on clean microscope slides, chemical compounds are extracted using optimized solvents, and the extracts are concentrated before GCxGC analysis.

The Analytical Workflow

- Sample Preparation: Fingerprints are collected and extracted with a solvent, designed to recover a broad spectrum of compounds. 

- Solvent Evaporation: The extract is concentrated using an Organomation MICROVAP evaporation system, ensuring efficient solvent removal without loss of target analytes. 

- GCxGC Analysis: The concentrated sample is analyzed using GCxGC coupled with sensitive detectors (FID and time-of-flight MS), providing detailed chemical profiles essential for aging models. 

The Role of the Organomation NITRO-GEN+

A critical component supporting this workflow is the nitrogen generator, which supplies high-purity nitrogen to both the GCxGC-FID and GCxGC-MS instruments. Here’s how the generator has transformed operations at C³AL:

- Reliable, On-Demand Nitrogen Supply: The generator provides a continuous, stable stream of nitrogen, eliminating the logistical challenges and safety concerns of handling high-pressure nitrogen cylinders. This is especially important for a lab running advanced instruments around the clock. 

- Operational Efficiency: With the generator, instrument uptime is maximized. There’s no need to pause research for cylinder replacements or refills—a common issue in academic labs, especially when building access or elevator outages disrupt deliveries. 

- Cost and Maintenance: Maintenance is straightforward and affordable—typically requiring a simple filter change once a year, as outlined in the manual. The generator’s mobility (thanks to built-in wheels) and user-friendly setup further streamline lab operations. 

- Sustainability and Safety: By eliminating the need for gas cylinders, the lab reduces its environmental footprint and enhances safety for students and staff. This aligns with C³AL’s commitment to sustainable, accessible research infrastructure. 

User Experience and Impact

Dr. Vozka reports that the nitrogen generator has been “very reliable” over more than a year of continuous use. The only minor drawback noted is operational noise, which the team mitigates by positioning the generator in an adjacent room when needed. Most importantly, the generator’s robust performance has enabled uninterrupted research and training, allowing students to focus on science rather than logistics.

“We opened the box, it has wheels, so we put it in place, connected everything, turned it on, and we don’t have to think much about it—which is pretty cool. It’s really so far a reliable generator.” — Dr. Petr Vozka

Conclusion: Empowering Innovation and Education

The NITRO-GEN+ nitrogen generator is a foundational asset for C³AL, supporting advanced forensic workflows and hands-on student training. By providing reliable, cost-effective, and sustainable nitrogen, it enables the lab to push the boundaries of analytical chemistry and forensic science—preparing the next generation of scientists for impactful careers.

For more on C³AL’s research and educational mission, visit their website: https://www.calstatela.edu/research/c3a