Innovative Technology For Trace Organic Analysis
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The most versatile and powerful thermal desorption unit

UNITY-xr™ is a world-leading analytical TD instrument for the simultaneous analysis of VOCs, SVOCs and thermally labile compounds collected onto sorbent tubes.

In contrast to other thermal desorption units, UNITY-xr quantitatively re-collects samples for re-analysis or storage, enhancing sample security. UNITY-xr also features an electrically cooled cold trap, dispensing with the expense and inconvenience of liquid cryogen.

Who uses the UNITY-xr?

UNITY-xr is perfect for any laboratory starting out in TD with low throughput requirements, or for those needing a versatile thermal desorber for all their TD applications (whether tubes, canisters, or on-line).


Product benefits

  • Peace of mind – with quantitative sample re-collection for repeat analysis, UNITY-xr offers simple method/data validation and overcomes the ‘one-shot’ limitation of other systems.

  • Enhance productivity with the world’s most versatile thermal desorber – UNITY-xr offers unmatched analytical performance for the widest range of TD applications.

  • Expand your capabilities – Not only does UNITY-xr allow you to analyse the widest possible range of VOCs and SVOCs in a single run, but the unbeatable split range (splitless to 125,000:1) enables both high-concentration and trace-level samples to be analysed on the same instrument.

  • Outstanding performance – Eliminate risk of discrimination, minimise artefacts and optimise data confidence, thanks to the fully inert flow path and backflush trap desorption.

  • Reduce running costs by avoiding the need for expensive and hazardous cryogen, and the associated risk of ice blockage of the flow path.

  • Easy and intelligent operation – With built-in parameters for several standard methods, automated self-checking diagnostics and usage/maintenance counters, you can quickly and easily get going and keep going.

  • Future-proof your lab – Additional modules allow automation of multiple tubes (up to 199), canisters and on-line samples, making UNITY-xr the perfect platform for expansion as the needs of your lab grow.

  • Be confident – You’re using a desorber that complies with key standards set out by numerous regulatory bodies, including US EPA, Chinese EPA, CEN, ISO, ASTM, HSE, JSA, NIOSH, and more.


  • Quantitative sample re-collection of all the split flows enables repeat analysis of critical samples and easy method validation.

  • An inert, optimised flow path allows quantitative recovery of C2 to C44, including reactive and thermally labile species... from percent to sub-ppt concentrations.

  • Rapid operation of the electrically-cooled focusing trap reduces costs and ensures fast sample throughput.

  • As well analysing 3½″ standard TD tubes, the UNITY-xr facilitates analysis of on-line, canister and bag samples through the modular addition of versatile accessories.

  • Method-compliance is aided by leak-testing and water management.

  • Advanced software control – Markes Instrument Control (MIC) is the only software designed specifically for thermal desorption users. Get the most out of your instrument with components such as automated intelligent diagnostics, leak isolation, usage and maintenance counters, rapid method set-up and customisable limits.

  • Compatible with all major makes of GC and GC–MS.

See our videos on

how to replace the focusing trap on the UNITY-xr

How to change the Split tube O-rings on the UNITY-xr

How to replace the fused silica transfer line to the GC

Markes International Ltd
Gwaun Elai Medi-Science Campus
Tel: +44 (0)1443 230935
Markes International GmbH
Bieberer Straße 1-7
63065 Offenbach am Main
Tel: +49 (0)69 6681089-10
USA (West)
Markes International, Inc.
2355 Gold Meadow Way
Gold River, Sacramento
California 95670
Tel: +1 866-483-5684 (toll-free)
Markes Instruments (Shanghai) Co., Ltd
Unit 1002, Building 1
No.418, Guilin Road
Shanghai 200233
P.R. China
Tel: +86 21 5465 1216
Part of Schauenburg International

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