The mobile system – about the size of a shoulder bag once complete – will consist of a silicon-chip-based gas chromatography column (GC column), a detector or sensor, integrated sample preparation, control and data-processing electronics and a power supply. “Gas chromatography (GC) is an analytical method used to separate, identify and quantify mixtures of substances. It’s suitable for gaseous or readily vaporizable compounds that don’t decompose on vaporization,” explains Olaf Hild. “A carrier gas first transports the sample through the GC column, which we’ve etched into a rapidly heatable and coolable silicon chip.” Inside the column, the gas molecules interact with the polymer-coated inner walls. The VOCs react with the inner coating depending on their affinity, and the mixture is separated. At the end of the chip-based GC column, a detector measures the substances separated by their molecular characteristics, generating a gas chromatogram with peaks that reveal the composition of the mixture. Fraunhofer IME handles the analysis of the measurement data. In the case of olive oil, the goal is to determine parameters, such as country of origin, age and purity level.
Initial tests successfully completed
Current tests using a conventional three-meter GC column demonstrate reliable separation of VOCs and enable effective sample analysis. GC columns in conventional, high-end laboratory gas chromatographs are often over 30 meters long and deliver higher separation efficiency, but this level of efficiency is not required for quality assessment of most foods. Among other challenges, the Fraunhofer researchers are working to design miniaturized GC columns capable of providing sufficient separation of VOCs specific to different foods.
“With our system we’re targeting non-specialists, such as bottlers and incoming-goods inspectors, who can easily operate the device after a short briefing,” says Tilman Sauerwald, a researcher at Fraunhofer IVV, where the demonstrators are currently being developed. “The components of our system can be adapted for specific applications, making it suitable for quality control in a range of different contexts, including the analysis of recycled plastics. We’re more than happy to work with industry partners to develop customized applications.”
The researchers will present some results of the project from March 24 to 27, 2026 at the Analytica trade fair in Munich at the Fraunhofer joint stand in Hall 3, Stand 312.
Fraunhofer PREPARE project PUMMEL
Point-of-use micro-multichannel gas chromatograph
Duration:
March 2023 through August 2026
Project funded by:
Fraunhofer program PREPARE
Project partners:
• Fraunhofer IME (validation and benchmarking)
• Fraunhofer IPMS (component concept for chip-based implementation, development of the GC separation column)
• Fraunhofer IVV (sample preparation, system electronics and integration)
Fraunhofer-Gesellschaft
