3.5 inch sorbent tube desorption (UNITY, ULTRA 50:50 & AutoSecure TD)

State-of-the-art DAAMS tube desorption

Some military and civil defence applications are best served by sorbent (DAAMS) tube sampling and off-line thermal desorption (TD) analysis using UNITY, ULTRA 50:50 or AutoSecure with laboratory GC/MS. The high-efficiency, electrically-cooled trap in UNITY delivers optimum capillary-compatible peaks offering sensitivities in the order of low picogrammes for target analytes. This means that detection limits below 0.0001 µg/m³ can be comfortably achieved with high volume (100-1000 L) tube-based sampling and enables compliance with the most stringent detection limits – for example, the current general population limit (GPL) for VX which is 0.003 µg/m³.

Markes range of thermal desorption systems are available in manual to fully automated (up to 100 tubes) configurations. Systems offer an inert, short and uniformly-heated flow path for compatibility with the most challenging analytes e.g. free-VX. They also feature stringent leak testing and a unique ‘SecureTD-Q’ facility. SecureTD-Q provides quantitative re-collection for repeat analysis thus allowing simple validation of the recovery of high boiling & reactive compounds. Both the leak test and SecureTD-Q are standard on all Markes tube-based TD systems and help ensure reliable data are produced. Markes systems feature electronic pneumatic control and advanced data-processing - incorporating the latest mass spectral deconvolution alogrithms. This ensures fast, accurate analysis, minimising false negatives and positives, and automatically generating a single, easily interpreted report.

45 pg of free-VX analysed without system passivation

  Key applications for Markes TD systems with sorbent (DAAMS) tube sampling include:

• Personal exposure monitoring (time weighted average)  
• Measurement of free-VX at trace levels 
• Fenceline monitoring of environmental concentrations with large volume air sampling for ultimate detection limits 
• Long term monitoring of decontaminated zones post-remediation 
• Confirmation of NRT analysis
  

For part numbers and pricing please contact your local Markes distributor.

Relevant technical support publications from Markes International can be automatically downloaded from this web site (registration required). Examples include:

• Brochures - UNITY, ULTRA, Air Server - Thermal Desorption Systems
• Brochure - Monitoring Chemical Agents
• TDTS 39 - Analysis of semi-volatile phosphorus pesticides using Mi thermal desorption systems - demonstration of method validation using SecureTD-Q
• TDTS 44 - The analysis of free-VX from sorbent tubes at low and sub-nanogram levels using a standard, non-passivated ULTRA-UNITY automated thermal desorber