What is the difference between the ATNA and GC-TEA?

Both the ATNA and GC-TEA use the same core detection technology: the 800 Series Thermal Energy Analyser. The difference is in how the TEA is used and what kind of answer each setup gives you.

ATNA: total nitrosamine screening

The ATNA heats a sample in a sealed headspace vial to release nitric oxide from any nitrosamines present. The TEA detects that NO and produces a single value representing total nitrosamine content. It does not separate or identify individual compounds.

This makes it a screening tool. It answers one question: are nitrosamines present above a given threshold? If the result is below the limit, the sample passes. If it flags, the sample moves to speciated analysis.

The system is fully automated. It holds 120 headspace vials, processes up to 10 samples per hour, and runs unattended, including overnight. Sensitivity is below 1 ppb total nitrosamines. No gas chromatograph is required.

GC-TEA: targeted, speciated analysis

In a GC-TEA configuration, the TEA connects to a gas chromatograph. The GC separates the sample into its individual components before they reach the detector, so each nitrosamine produces its own peak on the chromatogram. This gives you identification and quantification of each compound present.

This is the approach required when you need to report exactly which nitrosamines are in a sample and at what concentration, as is typically the case under regulatory frameworks such as ICH M7.

How they work together

In many laboratories, the two setups sit side by side. The ATNA screens large batches quickly. Any sample that flags moves to GC-TEA for full speciated analysis. This keeps throughput high without compromising the detailed reporting needed for compliance.

Detection of unknown nitrosamines

Because the TEA responds to nitrogen-containing compounds rather than to specific molecular targets, both setups detect nitrosamines that were not expected or not included in a reference standard set. The ATNA captures them in the total value. GC-TEA shows them as visible peaks on the chromatogram, even if they cannot yet be identified. This gives both approaches an advantage over methods that only detect compounds you are already looking for.

Which do you need?

If you need to screen large numbers of samples for total nitrosamine content, the ATNA is the starting point. If you need to identify and quantify specific nitrosamine compounds, you need a GC-TEA setup. Many laboratories use both.

Get in touch and we can advise on the right configuration for your workflow.