Articles and Applications
1. Gas Source Helium is becoming increasingly expensive with reports of its price having doubled in some regions between 2013 and 2015. Added to its increased price, supply cannot be ensured in certain regions which is increasing the number of labs looking to change to hydrogen.
Background Researchers from Prof. Guido Verbeck’s group at the University of North Texas (UNT) carried out analysis of drugs of abuse (DOA) and explosives using an ion trap GC-MS to compare results when using helium and hydrogen carrier and buffer gas. As well as comparing the two gases, the group also assessed a number of ion volumes with different orifice diameters to look at their effect on sensitivity with either gas.
Talk of a helium crisis following the shortage of 2012/13 appears to have subsided thanks to increased worldwide production, with labs now readily able to obtain helium. Here we look at what has happened over the last 2 years since the global helium shortage was the hot topic in GC, where do we currently stand and what is the outlook in the short term?
Results are used in court to provide quantitive levels of BAC, which makes it one of the most commonly practised analyses in forensic laboratories. The large number of samples and requirement for speed of sample processing mean that analysis needs to be conducted quickly, whilst giving reliable and accurate results.
Changing carrier gas from helium to hydrogen does not always present an opportunity for faster sample analysis. Method revalidation can be simplified by keeping the new method as close to the old method as possible, which will limit changes to sample selectivity and resolution whilst maintaining the retention times of analytes.