MassFinder Options - options

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MassFinder 4: Manual

This page explains the options tab sheet of the options dialog.

Contents

Additional options

show relative retention time

The relative retention time (RRT) is defined as the ratio of the retention time of a scan and the retention time of an internal standard. Thus, the internal standard has the RRT 1.0. The releative retention time is a simplified and somewhat coarser alternative to retention indices. Retention indices require a whole series of alkanes used as standard compounds which are usually applied as external standards, i.e. alkanes and sample are not mixed but measured after each other. In contrast, RRT usually require an internal standard mixed with the sample.

If this options is activated, MassFinder will display the RTT in all mass spectra below the line of retention indices: top retention time, center retention index, bottom relative retention time.

In order to use this feature you need to define the retention time of the internal standard. You can define the internal standard by first selecting the internal standard as current scan, then using the tools dialog, where you can click the RRT button in order to define the internal standard and automatically calculate the relative retention times of all scans.

show library structures

The Terpenoid library comes with a graphical structure for each entry. When creating your own libraries, you can add a graphical structure to each entry by pasting it from the clipboard into the MassFinder library entry dialog.

If this option is activated, MassFinder will show the chemical structure in the highlighted current library entry on the right panel. If deactivated, MassFinder will not display the chemical structures.

Personal field

Each library entry contains a personal field which can be used for whatever you want, e.g. company registration numbers, substance identification numbers, order of retention or many other information relevant to you. If you have no idea at the moment, just leave this field empty and ignore it.

In order to ease the use of this field, you even may give it an individual name. Enter any reasonable, short name that describes the information well into the name of personal field edit box. By default, MassFinder uses the name ID for the personal field. You may rename the personal field whenever you want.

You can use the personal field content to label peaks in the main view's profile or in the Export chromatogram dialog.

show ID in front of name

Some usages of the personal field may profit from displaying the personal field contents in front of the chemical name in the main view's mass spectra.

write name of personal field in front of its value

If you activated the previous option, you might want to indicate what kind of information is being displayed in front of nthe chemical name, e.g. ID.

label peaks with ID

If this option is activated, the marked peaks in the main views's profile will not be labelled with retention times, but with the content of the personal field.

Gerstel Olfactory Detector Port

If your mass spectrometer is equipped with an olfactometric detector ("sniffing detector", Latin olfacere, to smell), i.e. an outlet that allows the human nose to sniff the eluting constituents, MassFinder can display the olfactogram as trace both in the main view's profile and in the Export chromatogram dialog.

MassFinder currently supports the Agilent implementation of the Gerstel olfactory detector port. The Gerstel ODP offers the sniffing outlet, an input device to indicate certain peaks, and a software add-on to Agilent ChemStation. The user can sniff the eluting constituents and dictate his sensoric impressions which are automatically voice-to-text converted and stored as additional data file together with the GC/MS data. MassFinder displays the indicated peaks and the text transcriptions of the dictated olfactory impressions.

The human nose is an extraordinary detector. Olfactometric detectors enable you to assign a specific smell to individual peaks, e.g. for identifying constituents causing an off-fragrance. There are also many constituents known which smell strongly but which not give a detectable mass spectrometic signal, not even at concentrations of many magnitudes more. Using olfactometric detectors drastically eases the sensoric interpretation of analytical results.

External link to manufacturer: Gerstel olfactory detector port Gerstel ODP or German customers: Gerstel ODP

open and display olfactogram

If this option is activated, MassFinder will automatically look for an ODP trace present in the native data file folder whenever you open a data file. If you do not use ODP, then please deactivate this option (default setting).

If you use ODP and do not want to view the ODP trace at the moment, please simply hide the trace by clicking on the little black square after the trace name in the upper right corner of the chromatographic profile. You do not need to deactivate this option to temporarily deactivate the visibility of the ODP trace.

show ODP labels in olfactogram

If this option is activated, MassFinder will display the sensoric impressions as text in the chromatographic profile.

show ODP labels in mass spectra

If this option is activated, MassFinder will display the sensoric impressions as text in the upper left corner of the mass spectra.

See also

Please select the tab sheet of interest:

Personal tools