Thermo Fisher Scientific has introduced an application note that demonstrates its range of offerings for the food safety industry.
The note also details its performance capabilities in the determination of low concentrations of pesticide residues.
The application note, entitled 'Quick Start-Up for a Modified Quick, Easy, Cheap, Effective, Rugged and Safe Multi-Residue Pesticide Analysis in Lettuce by GC/Msn', details sample preparation methodology and instrumentation guidelines to achieve pesticide determination with increased accuracy using the Thermo Scientific ITQ 700 ion-trap mass spectrometer.
When used in combination with the Thermo Scientific Focus GC, the ITQ 700 GC/MS achieves an average relative standard deviation of 9.7 per cent of four replicate analyses at 50 ng/g and a calculated average limit of detection of 2.7 ng/g in iceberg lettuce, based on eight replicate analyses of 5 ng/g, below all published minimum reporting limits.
The elevated injection flow rate provided by the Focus GC reduces target compound interaction with the injection port liner, minimising the breakdown of targeted fragile pesticides and increasing result accuracy.
In addition, this reduction in breakdown of targeted fragile pesticides permits less frequent replacement of consumables and reduced maintenance downtime.
When operated in the Msn mode, the ITQ 700 performs tandem MS functions by injecting ions into the ion trap and destabilising matrix ions, isolating only the pesticide ions, which are then given sufficient energy to further fragment.
Through this efficient elimination of detrimental matrix interferences, plus the capabilities of GC/MS, an enhanced product ion spectrum of the target pesticide is achieved with more accurate results at lower concentrations.
