Spektraris searches user-input LC-MS data against an LC-MS database of about 500 plant natural products.
Search criteria are listed below. Make sure to enter values for tolerance (if applicable) and the appropriate unit for the tolerance.
Relative retention times for LC data in the database have been determined relative to anthracene-9-carboxylic acid as an internal standard. Find the retention time of anthracene-9-carboxylic acid in your chromatographic run and type it into the appropriate field. Relative retention times are calculated by dividing the retention time of a detected mass peak by the retention time entered for anthracene-9-carboxylic acid. If you did not add anthracene-9-carboxylic acid as an internal standard, you should check the box for ‘Retention Time’.
LC-MS data should be pasted into the box at the bottom as tab-separated values with the first line containing “ID”, and one or more of the following labels: “RT”, “Exact_Mass”, “m/z”, “Formula”. The subsequent lines should contain data beneath the appropriate heading, one feature per line. The easiest way to enter data is generally to delete the default contents of the Input box, then copy and paste in your data from a spreadsheet program.
Results are limited to 10 hits per feature. Hits are ordered by the parameter selected for the 'Sort Hits By' option. The closest hit is listed leftmost. If searching only by formula, results are not sorted. Input is limited to about 500 kb, which usually corresponds to about 2500 mass peaks.