Category Archives: method settings
FreeStyle tutorial: Averaging Spectra
The video below demonstrates how to average mass spectra inside of a workspace, through annotated click-through text.
FreeStyle tutorial: mzVault Searches
The video below demonstrates how to perform mzVault library searches of spectra, through annotated click-through text.
Video – How to create NIST 2014 custom libraries with FreeStyle
To make custom libraries for use in TraceFinder 3.3 Unknown Analysis, the easiest way is to curate your spectra with FreeStyle and send to the NIST 2014 application which comes with the purchase of any NIST 2014 library.
Retention Time Reference Compounds Used For Correcting Chromtographic Drift
TraceFinder has an option to allow the user to set a reference compound to assist in corrections of retention time drift.
The feature is the same implementation that has been a part of the Xcalibur feature set for over 20 years and is well characterized. The user simply selects a checkbox in the RT Reference compound column of the Method – Identification tab. This sets the compound for use in linking other compounds to its found RT.
To set a compound to use a RT reference compound, simply select a RT Reference from a dropdown selector in the same definition grid.
The typical use of this feature is to set your Internal Standards as RT Reference Compounds and then link the nearby eluting components to the Reference Compound. Also, the IS retention time peak detection window is set a little larger than the target components to allow for detection if a large RT drift occurs.
When the RT reference is detected the difference, whether + or – in time are adjusted in the connected compounds. This new RT is specific to each compound in each sample. Therefore it is not reflected as a change in the method because the method is set as a batch level setting. The compound using the RT reference must have an original expected retention time to be adjusted, it cannot be left as zero for this feature to work.
TraceFinder: Direct Knowledge 