Technology
HT-IMS module
TeChBioT pursued a high-temperature, dual-polarity IMS concept that can operate at elevated temperatures (≥200 °C) to improve compatibility with low-volatility compounds and reduce surface adsorption effects. It resulted in a compact architecture with dual polarity and ionization with soft X-ray.
Development showed that high-temperature IMS performance is dominated by two coupled issues:
Thermal non-uniformity and gradients.
The project observed artefacts such as peak splitting (double peaks) attributed to temperature gradients along the drift region. This required iterative redesign because even small spatial temperature differences change ion mobility and distort peak shape, directly degrading identification reliability.
Materials compatibility and outgassing.
At elevated temperature, trace outgassing and contamination can alter reactant ion chemistry and baseline stability, creating drift-time shifts, nuisance peaks and reduced repeatability. The document notes outgassing issues in high-temperature implementations and describes a progression toward more suitable high-temperature constructions and materials (including alternatives such as PEEK-based concepts and oven-style heating strategies).
TeChBioT addressed thermal artefacts through a combination of experimental iteration and modelling/simulation.
Redesigned inlet and outlet heating concepts, together with the evaluation of “oven-like” stabilisation strategies, were implemented to reduce temperature gradients across the drift tube.
In parallel, the module design evolved toward high-temperature material choices and configurations that minimise outgassing and improve long-term cleanliness at elevated operating temperatures.
Demonstrated Performance
Within the stated conditions, the HT-IMS module achieved a resolving power of around 70.
The system was validated in representative low-level detection demonstrations, supporting the feasibility of HT-IMS for low-volatile chemical detection when thermal control and cleanliness are properly maintained.
Key Operational Insight
Reliable HT-IMS operation depends on temperature-field uniformity and materials cleanliness as much as on electrical design. Both directly influence peak shape, drift-time stability and nuisance features.
Operationally, disciplined sampling and injection control is essential for repeatability, particularly in mobile and outdoor deployment scenarios.
HT-GC module development and coupling with HT-IMS
TeChBioT pursued a miniaturised high-temperature GC concept that can be integrated into compact field systems and paired with HT-IMS as detector. A modular separation unit was built around compact GC components and operationally relevant utilities, such as controlled carrier-gas supply using scrubbed air and moisture management. Development highlighted that high-temperature operation changes the dominant engineering risks compared with conventional compact GC.
Two issues became particularly important in the TeChBioT work:
Thermal robustness and stability.
Maintaining stable retention behaviour and reproducible transfer to the IMS requires tight control of temperature profiles and minimisation of cold spots and adsorption sites across the separation path and the GC–IMS interface.
The coupling work in TeChBioT treated the GC–IMS interface as a system boundary that must preserve both chromatographic integrity and IMS ion chemistry stability. The coupling concept links a compact HT-GC separation stage to the HT-IMS drift tube so that separated analyte bands are delivered to the IMS under controlled flow and humidity conditions. This pairing leverages the strengths of both techniques: GC reduces chemical complexity and co-elution, while IMS provides rapid, sensitive detection and supports fast decision logic once compounds have been separated in time.
TeChBioT iteratively improved the HT-GC-IMS concept through design refinements that focused on thermal design and material selection. The project’s learning around high-temperature outgassing and stability informed the move away from less suitable constructions toward more appropriate high-temperature materials and heating strategies intended to reduce contaminant release and stabilise performance over time. Moisture control and carrier-gas conditioning were treated as enabling elements because they directly affect both chromatographic performance and IMS baseline chemistry.
Key Operational Insight
High-temperature GC-IMS performance depends strongly on interface cleanliness and thermal management, because any outgassing or temperature instability propagates into IMS reactant-ion chemistry and baseline stability. For fieldable systems, carrier-gas conditioning and humidity control are not auxiliary features but core enablers of repeatable retention behaviour and interpretable IMS signatures in complex environments.
Pyrolysis–GC–IMS module development
The final system integrates three elements into one operational workflow:
1. Pyrolysis
A pyrolyzer generates volatile pyrolysates from solid, swab, filter, powder, soil or concentrated liquid samples.
2. Gas Chromatography (GC)
A GC stage provides temporal separation of the complex pyrolysate mixture.
3. HT-IMS Detection
HT-IMS detects the eluting compounds, producing fast, information-rich signatures compatible with classification workflows.
This architecture is explicitly designed for field compatibility and modular deployment, including vehicle-based and mobile-laboratory use, rather than laboratory-only operation.
Core Engineering Achievement
The central engineering achievement was the development of a low-cost Curie-point pyrolyzer.
Curie-point induction heating was selected because it provides a practical balance of:
Simplicity
Energy efficiency
Operational robustness
An oxygen-free, nitrogen-flushed process was developed, together with a stepwise operating procedure that includes a pre-drying step to remove water prior to pyrolysis. This reflects operational reality, as water-rich samples are common in biological response scenarios.
Key technical challenges encountered
Pyrolysis-based bio detection introduces challenges that are distinct from chemical vapour sensing:
Matrix complexity and concentration dependence.
Biological materials produce dense, overlapping pyrolysis product mixtures and the resulting fingerprint depends on biomass amount, sample state and co-extracted matrix components. This makes repeatable sample input and preparation essential for classification reliability.
Workflow integration.
The project treated sample handling and pre-processing as part of the analytical system, because the pyrolysis step amplifies differences in how samples are collected, dried and loaded. TeChBioT therefore developed handling routes for liquids and for matrix/surface samples such as swabs and filters.
Key Operational Insight
Fieldable biological detection with pyrolysis depends as much on controlled sample handling and reproducible pyrolysis input as on instrument performance. Biomass amount and matrix co-load directly shape the resulting fingerprint.
Combining pyrolysis with (HT-)GC separation and IMS detection creates signatures that are sufficiently rich for AI/ML classification, enabling rapid triage in scenarios where classical single-marker approaches are not realistic.