Markes International (Llantrisant, UK) has released a new sorbent tube dedicated to the reliable analysis of polycyclic aromatic hydrocarbons (PAHs) in air.
The new ‘PAH tube’ is the outcome of a detailed optimisation process for the analysis of these highly challenging analytes, which are subject to very low limit levels worldwide because of their carcinogenic properties.
Ilaria Ferrante, Markes’ Marketing Manager for Consumable Products, explains the need for the new tubes. “Existing solvent-based techniques for analysis of PAHs in air are labour-intensive and prone to loss of analytes. Using our new optimised thermal desorption tubes for the analysis of PAHs brings the big advantage of full automation to this challenging application, as well as the outstanding sensitivity inherent to thermal desorption”.
The new tubes ensure the transfer of even the heaviest PAHs from the sorbent sampling tube into the GC. Ferrante says “Contamination of the analytical system can be a big problem when analysing these very high-boiling compounds, but using the optimised sorbent tubes with our UNITY or TD-100 instruments gives negligible carryover across the board, as well as excellent reproducibility.”
Added advantages, says Ferrante, are the convenience of needing significantly lower sampling volumes than for solvent-based techniques, simplifying the sampling process. She also points out that thermal desorption interfaces with the same type of GC–MS analytical equipment widely used for monitoring VOCs such as benzene in ambient air, meaning that laboratories needing to analyse PAHs can easily incorporate the reliable analysis of PAHs into their existing workflows.
Details of the new tubes and the optimised thermal desorption protocol, along with full performance data, are available in Markes Application Note 115, which is downloadable from Markes’ website (www.markes.com).