Agilent updates hardware and software on Q-TOF GC/MS system
The firm said the 7200B offers extended mass range, improves mass accuracy and stability and software capabilities, with focus on the pesticide screening software tools.
It replaces the company’s most advanced GC/QTOF, the 7200A which was launched in 2011.
GC/MS is commonly applied to volatile and semi-volatile compounds, said Terry Sheehan, Agilent’s director of marketing for GC/MS products.
Use of tech
Semi-volatiles include hundreds of pesticides and other compounds of interest to environmental, toxicology, and chemical/energy applications.
“For some compounds, GC/MS is preferred; for others, LC/MS is a better choice. But there are many semi-volatile pesticides that can be analyzed by either GC/MS or LC/MS,” he told FoodQualityNews.com.
“The GC/Q-TOF with the new Personal Compound Database Library (PCDL) makes screening easier and provides additional confidence with high resolution-accurate mass information.
“The GC/Q-TOF is also capable of analysing unknown components that are not present on target lists or in the spectral database.”
Food safety demand
John Lee, Agilent’s food safety global market manager, said labs are constantly looking to simplify the way food samples are prepared for analysis to save cost and increase productivity so more samples can be surveyed.
“In the past, lower cost GC/SQ (single Quadrupole) MS dominated many food safety labs, but the limited selectivity of unit-mass resolution MS requires that all traditional steps of extract clean-up (and even pre-enrichment prior to analysis) be maintained,” he said.
“Today, most labs are replacing GC/SQ with GC/TQ (tandem quadrupole; triple quadrupole) since the selectivity of MS/MS allows consistently lower detection limits eliminating need for pre-enrichment steps and offering opportunities for new smarter sample clean up approaches.”
GC/TQ MS/MS is powerful and very sensitive but it only detects what it was programmed to, said Lee.
“The 7200B GC/Q-TOF also achieves the above advantages of selectivity but can detect targets (lab has a calibration standard), non-targets (no standard, but a spectral database to screen against) and even unknowns (no standard, no database),” he said.
“Not only does this address the increasing demand to cover more potential threats in our food but it does so whilst allowing the labs to only calibrate the instrument for the ‘usual suspects’.
Lee said in a world of limited resources this is key because calibrating for everything would just cost too much in standards.
“And if something suspicious comes up which isn’t on even the screening database, the 7200B GC/Q-TOF has the ability to decipher its structure using the information power of high-resolution, accurate mass MS/MS experiments,” he said.
“Indeed, for a new compound of concern that no-one previously thought of, it’s then also possible to perform retrospective investigations of previously analyzed samples, since the complete spectral dataset is saved.”
Mass accuracy and range
The Agilent 7200B system provides improved mass accuracy specification of less than 3ppm and an extended mass range.
This will allow for analysis of larger mass compounds and benefits when coupled to Thermal Separation Probes (TSP) or Direct Injection Probes (DIP).
Other enhancements include Chemical Ionization Source and Backflush capabilities as standard on all GC/Q-TOF systems.
Agilent’s pesticide PCDL includes compounds with exact mass spectra and retention time information for three different GC configurations.
Sheehan said that TSP and DIP are sample introduction techniques
“Many high mass compounds will not pass through a GC column and require a more direct injection technique to be analysed,” he said.
“The 7200B GC/Q-TOF has extended mass range capabilities the enable the analysis of these higher mass compounds (> m/z 1,000).”
However, the absence of a separation is also a limitation, he added.
“DIP works well for pure standards, but not for trace analytes in a complex matrix. TSP can be configured with a short GC column to eliminate some matrix interferences, but that is not equivalent to a high performance GC separation before the MS.”
