For instance, the probability that any of a range of substructures are present or absent are listed phenyl, acid, ester group, double bond, heteroatom, etc. This tool was developed to aid NIST evaluators in their analysis of mass spectra. In one integrated program, it permits a wide range of calculations on a mass spectrum using--if available--a proposed chemical structure.
Spectra and structures are associated in the library facility of the Windows Search Program discussed above, and the program is activated from the Tools menu. Peaks in the spectrum originating as a logical fragment of the molecule are marked, and corresponding fragments may be highlighted.
It also allows the analyst to keep track of important neutral losses, both from the parent or a derived ion, and to readily compute possible formulas for any peak or neutral loss and isotopic patterns as desired.
Observed isotopic clusters can be compared to theoretical predictions subject to a number of user-specified constraints. The above list is somewhat of a moving target. Please drop us an e-mail if anything here is incomplete. The demo differs from the full version of NIST mainly in that it contains a very small subset of the EI database and a somewhat older version of the software about spectra. L format , although you can load Agilent. Which version to buy?
Call or e-mail us if you have any questions about which version to buy. In summary:. Other databases available: The NIST mass spectral database is a strongly validated and extensively used MS library of general compounds recommended for most all users. Users looking for a larger library or libraries dedicated to certain classes of specialty compounds may wish to augment their NIST database with one of the Wiley MS libraries.
Catalog AA MS Heaters and Temperature Sensors. Agilent Heaters and Sensors. Hover over image to zoom. About Major Enhancements in from Major Enhancements in from Notice to licensed NIST users. The GC Database is also available separately at very low cost, so you can provide it to each of your chemists to run on their desktops.
New features of the NIST 17 program and database are: EI Library Expansion: Significant expansion of coverage of metabolites and designer drugs in the EI library, as well as the application of new computer-assisted evaluation methods for removal of low quality spectra.
Spectra include metabolites, peptides biologically active peptides and all di-peptides and tryptic tri-peptides , contaminants, metabolites, lipids and more. New 'Hybrid Search' search type for all spectrum types, enable finding many more similar compounds in the hit list. It requires a precursor mass.
New neutral loss search is available that eliminates restrictions on the maximum loss considered. Improved algorithms for scoring high mass accuracy searches that account for sparse spectra. Peaks shifted in the 'Hybrid Search' are shown before and after shifting.
Hybrid searching uses both the logic of normal searching plus the logic of neutral loss searching. Rejects spectra which do not have correct Precursor type syntax. Finds all spectra which have the same first InChIKey segment as the search spectrum, and compares them to the search spectrum. When a spectrum is associated with a structure in the Spectrum Information dialog box of the Librarian tab view, the InChI Key is automatically associated with the spectrum.
Columns in any Hit List can be positioned as desired. Update list of libraries may be performed without exiting MS Search.
This includes third party libraries like the Wiley Registry. Structure Search Database Builder updates user library structure indexation. A new version of MS Interpreter allowing for high accuracy mass spectra and exact masses for fragment ions.
Retention indexes in some of Main and Replicates libraries spectra. Automatic Retention Index estimation from chemical structure right-click spectrum text window, select Properties, Retention Indices. Polar columns were new to the release.
Structural replicates display in addition to usual CAS number matching in Main and Replicate libraries, including a new feature: displaying derivatives and a wider range of tautomers. Select matching method in Options, Replicates. Structure searching - the program will find all chemical structures similar to the structure of the search spectrum.
The searching can be done using structural data from the NIST MS database, from the user database or from a structure drawn in most chemical drawing packages. A structure may be exported to chemical drawing software. The Structure similarity search algorithm has been changed: now it includes homologue recognition that generates a match factor of for homologs.
You will need to rebuild structure search databases in user libraries as you usually need to do after editing a user library containing structures. Drag and Drop - Data can be dragged and dropped between windows.
Point mouse to the name of the compound in the spectrum plot window, press and hold the left mouse button, drag the spectrum and drop it into Spec List or Compare Window. User Library Structures - This feature has been present for some time, but many are unaware of it.
Compare Views - There are a number of different ways for you to visually compare two spectra. Direct interaction with a number of chemical drawing packages - the clipboard can be used with some of them, most can be used by use of intermediate files.
Look at the context sensitive options on the right mouse button click and on buttons at the top of the window.
Thermodynamics-based MS Interpreter program version 3. This program now works for both low and high mass accuracy spectra and permits using a mouse to select parts of a chemical structure for mass and formula determination and analysis. EI MS Library: Spectra for nearly 30, new compounds have been added since the version, with increased attention to adding metabolites plant and human , drugs, and compounds of industrial and environmental importance.
Emphasis has been put on spectra for a wider range of derivatization methods. Extensive improvements in chemical names, structures and replicate spectra have also been made, with particular attention to improving naming for derivatives. With an increased focus on adding all possible precursor ions, this had led to an increased in the number of precursor ions by a factor of three relative to the version with a near doubling of the total number of spectra to K.
All new spectra were acquired at high accuracy and resolving power, over a range of energies, and in both collision cells beam type and ion traps up to MS3 in both positive- and negative-ion mode, when appropriate. A large proportion of these new compounds are metabolites, both from plants and humans. Spectra include metabolites, peptides biologically active peptides and all di-peptides and tryptic tri-peptides , contaminants, lipids and more. Advanced noise removal processes have improved the quality of a number of spectra that appeared in earlier versions.
Each spectrum contains extensive annotation, and now user libraries can be created with the same degree of annotation. GI RI Library: RI data are provided for over 82, compounds, an increase of over 12, compounds from the version. Other Products and Services. Interlaboratory Study.
Thermochemical data tables. ASMS ASMS Upcoming! Peptide Libraries. Download Libraries. Oligosaccharide Libraries. Human Milk. Mammalian Milk. Antibody Libraries. Contact: massspec nist. Table of Contents Download. Mass Spectrum Interpreter Version 2. Only a manual uninstall of the update by restoring the backup files is possible. Please read this document before downloading the complete zip file.
Further, NIST does not endorse any commercial products that may be mentioned on these sites. Please address comments about this page to nvd nist. Please let us know. You are viewing this page in an unauthorized frame window. Email List FAQ.
Categories Data Feeds. Vulnerabilities Products. Terms of Use.
0コメント