Productivity-Enhancing Improvements to Range of Thermal Desorption Instruments Announced

Markes International (UK) has recently announced the latest technological improvements to its range of thermal desorption (TD) instruments, which further extend the application range and enhance productivity.

The first improvement is to allow much higher-concentration samples to be analysed in the same sequence as low-concentration samples. The new changes mean users can allow only a tiny fraction of the original sample into the analytical instrument. Markes’ Product Manager, Steve Davies, explained “The enhanced electronic mass flow control technology now implemented across Markes’ range of thermal desorbers allows split ratios from zero to 125,000:1 for routine TD–GC methods. This uniquely wide range also means more samples can be automatically and quantitatively re-collected for repeat analysis and method validation. These new capabilities are especially useful for key applications such as workplace air monitoring, industrial emissions testing and materials analysis”.

The second improvement has been to speed up cooling and reduce thermal desorption cycle times, with or without re-collection, thus boosting the number of analyses that can be undertaken in any given period. Davies said “Our customers frequently tell us that sample throughput is crucial for them, and many are looking to use new fast GC methods. The new reduced TD cycle times complement this, making sure thermal desorption doesn’t become the ‘rate-determining step’ in the process”.

In addition to the instrument enhancements, Markes has also announced improvements to its SafeLok TD sampling tubes, which already set the standard globally for pumped air monitoring tubes. SafeLok tubes can be used interchangeably with standard tubes. They have the same external dimensions and sorbent masses, but are protected with diffusion-locking technology at both ends, which stops contaminants getting in and analytes getting out. Steve Oldfield, Markes’ Consumables Product Manager, said “Everybody likes the extra sample security offered by SafeLok tubes, but now they can be used at higher sampling flow rates and with standard pumps, they’re suitable for all pumped air monitoring applications”. He went on to say “No-one likes to repeat expensive field monitoring exercises, and SafeLok tubes help guarantee this by minimising any chance of accidental loss or contamination of samples before, during and after sampling.”