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The NIST 08 Mass Spectral Library (NIST/EPA/NIH)--New 2008 Version
Figure: EI spectra, structure, and
corresponding data for a sample compound in the NIST database.
--The fully-evaluated, most widely used mass spectral reference library. Compiled by the National Institute of Standards and Technology (NIST). Ship Date: NIST 08 is shipping approximately Aug. 1, 2008. Anyone ordering NIST after May 1, 2008 will be shipped the new 2008 version upon release. Summary: The NIST 08 mass spectral database, the successor to the NIST 05, is a fully evaluated collection of electron impact (EI) mass spectra. It also contains MS/MS spectra and GC data. It is the product of a two decade, comprehensive evaluation and expansion of the world's most widely used mass spectral reference library by a team of experienced mass spectrometrists in which each spectrum was examined for correctness. NIST ComponentsNIST is not just a mass spectral library. It contains these components:
Libraries are formatted the binary format suitable for use alone or by the NIST MS Search software (and AMDIS). Additional instrument-specific formats (e.g. Agilent ChemStation) are available separately to permit library searching directly within your GC/MS or LC/MS data system. With each purchase, we ship a CD (installs software, libraries, and documentation) and a printed manual. Summary StatisticsStatistics for NIST 08 and earlier versions are given below.
(*) plus quality improvements See also What's New in NIST 08. Electron Impact (EI) mass spectral libraryThis is a "fully evaluated" collection of electron impact (EI) mass spectra. It is the product of a two decade, comprehensive evaluation and expansion of the world's most widely used mass spectral reference library by a team of experienced mass spectrometrists in which each spectrum was examined for correctness. This has lead to thousands of selections, deletions and modifications to produce an optimal reference library of compound identification by spectrum matching and library searching. Each spectrum has been carefully evaluated, and all decisions regarding selection or deletion were made only after agreement of two experienced mass spectral evaluators, as described in presentations at major conferences. While computer methods assisted in finding chemical identification errors and inconsistencies, and revealed certain varieties of mass spectral errors, manual interpretation was the principal basis for this evaluation effort. The Electron Impact (EI) mass spectral library consists of 220,460 spectra of 192,108 unique compounds, most of which include chemical structures and related data. Besides spectra, typical data include name, formula, molecular structure (.mol), molecular weight, CAS number, contributor name, list of peaks, synonyms, and estimated retention index. Name: 1-Decanol Formula: C10H22O MW: 158 CAS#: 112-30-1 NIST#: 227969 ID#: 17833 DB: mainlib Other DBs: Fine, TSCA, RTECS, HODOC, NIH, EINECS, IRDB Contributor: Japan AIST/NIMC Database- Spectrum MS-NW-4441 10 largest peaks: 55 999 |43 988 |56903 |70894 |41776 | 69 725 |83 549 |57462 |84397 |42371 | Synonyms: 1.Decyl alcohol 2.n-Decan-1-ol 3.n-Decanol 4.n-Decyl alcohol 5.Alcohol C10 6.Alfol 10 7.Capric alcohol 8.Caprinic alcohol 9.Decanol ...22 other names... Estimated non-polar retention index (n-alkane scale): Value: 1258 iu Confidence interval (Alcohols): 41(50%) 176(95%) iu The NIST EI Library focuses on:
Here is a breakdown by mass:
The best quality spectra are placed in the Main Library; and good-quality, alternate spectra are provided in the Selected Replicates Library. NIST 08 includes a separable collection of 717 spectra of 672 salts and low-volatile substances not expected to be measurable by GC/MS (nist_salts). Here's a breakdown by mass:
To check whether certain compounds or classes of compounds exist within the NIST 08 database, you may do an online search of compounds in the NIST 08 database. NIST spectra have been obtained from thousands of sources. Major sources include # Spectra, Name 29410 A.A.Kutin, Moscow, Russia 28787 Zaikin V.G., Borisov R.S., L.N.Kulikova, TIPS RAS / RPFU / Russian ..... Friendship University / Topchiev Inst.Petrochem.Synth., Moscow, Russia 26548 Chemical Concepts 13336 Japan National Institute of Advanced Industrial Science and Technology (AIST) ..... / National Institute of Materials and Chemical Research (NIMC) ..... Database- Spectrum MS-IW-1026/MS-NW-9250 9594 NIST Mass Spectrometry Data Center 7657 Div. of Experiment Therapeutics, Walter Reed Army Institute of Research ..... (WRAIR), Washington DC 5586 National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK), ..... National Institutes of Health (NIH), Bethesda, MD 4163 A.T.Lebedev, Moscow State University 2683 ASES Database, Dalian Institute, P.R. China 2376 Carl Djerassi, Dept. Chemistry, Standford University, Stanford Calif. 2360 Asinex Ltd, Moscow, Russia 2205 D.Henneberg, Max-Planck Institute, Mulheim, Germany 2182 Institute of Organic Chemistry, Novosibirsk, Russia 1789 A.Mazepa, Phys.-Chem.Institute, Odessa, Ukraine 1528 Humboldt-Universitat zu Berlin, Department of Chemistry, Analytical Group 1481 A.Pleshkova, Nesmeyanov Inst.Org.Elem.Cpds, Moscow 1091 Organic Synthesis Lab, MSU, Moscow 1066 William W. Christie, Mylnefield Lipid Analysis, Invergowrie, Dundee, Scotland, UK MS/MS LibraryMost of the MS/MS spectra have been measured on ion trap and collision cell instruments using electrospray ionization, although spectra from a number of other instrument types and ionization methods are represented. Spectra have been provided by contributors, measured at NIST and extracted from the literature. In view of the relatively small size of the library, it is intended primarily to serve as a 'starter set'. It also documents spectrum variations between instruments classes at different conditions. We have found that at sufficiently high signal-to-noise measurement conditions, modern instruments are capable of providing very reproducible, library searchable spectra. While collision energy can be an important variable, spectra varies in an understandable way depending on compound and instrument class and conditions. This Library is provided in formats equivalent to the Electron Ionization Library but with new fields added to describe the instrument and analysis conditions. A small number of MS1 spectra are also included for reference purposes. These generally contain the ions used for MS/MS. The search software permits the examination of all MS/MS spectra - these are available as a selectable library, with the name 'nist_msms'. A new MS/MS tab has been added to the MS Search Software to view that data. Gas Chromatography (GC) Data LibraryGas phase retention data for compounds common to the EI and NIST Retention Data collection are provided with links to the EI library. This involves 192,108 Kovacs indices and corresponding GC column conditions and literature citations for 21,847 compounds, an increase of over 50% from the previous version. Data include both non-polar and polar columns. Most values were abstracted from the open literature and then compared to replicate values (average of 10 per compound) and estimates to find and remove errors. We also continue to provide estimates of retention indices for most compounds in the library using an extension of a method developed earlier for boiling points [2-3]. GC data includes
Here's typical GC data included for a compounds (decanol): Estimated non-polar retention index (n-alkane scale): Value: 1258 iu Confidence interval (Alcohols): 41(50%) 176(95%) iu Retention index 1. Value: 1256 iu Column Type: Capillary Column Class: Standard non-polar Active Phase: CP-Sil PONA GB Column Length: 100 m Carrier Gas: He Column Diameter: 0.25 mm Phase Thickness: 0.25 um Data Type: Linear RI Program Type: Ramp Start T: 140 C End T: 230 C Heat Rate: 5 K/min Start Time: 10 min End Time: 25 min Source: Cunicao, M.M.; Lopes, A.R.; Ccco, L.C.; Yamamoto, C.I.; Plocharski, R.C.B.; Miguel, M.D.; Junior, A.G.; Auer, C.G.; Miguel, O.G., Phytochemical and antibacterial evaluation of essential oils from Ottonia Martiana Miq. (Piperaceae), J. Braz. Chem. Soc., 18(1), 2007, 184-188. ...152 additional retention index citations follow... The GC data is useful not only for the GC retention index values but also for the GC column conditions and cited literature that goes with it.
References: NIST MS Search Software
The updated, full-featured NIST MS Search Program for Windows has a full range of integrated tools. The new updated version of this widely used, full-featured software is designed for identifying compounds from their mass spectra and for exploring mass spectral libraries. It also contains tools for deconvoluting gas/liquid chromatograms and interpreting mass spectra.
OverviewThis software provides a flexible means of accessing data in the NIST and User libraries including:
When the program is first started, seven tiled windows appear on the screen (the Desktop), each with its own data and behavior. The behavior of any Window may be modified by making it active (clicking on it) and then pressing the AdjustWin button at the bottom of the Desktop. As you become familiar with program operation, you may wish to change the dimensions of some Windows or even close some of them to create a custom Desktop. When the program is restarted, it will begin with the most recent Desktop. To save a window-arrangement Desktop for future use, select Desktop from the Menu Bar and then Save As… from the resulting Menu. Prior Desktops may be restored using one of the predefined names or your own name. Such arrangements describe the geometry and type of information shown in each Window, not the actual data contained in it. To restore a previous hit list, select it from the list at the top of the Hit List Window. Library Searching - Identify unknown compounds and substructures using fully documented and optimized procedures, or search by a wide range of compound and spectral properties. Library Building - Maintain your own libraries, add your own chemical structures and search using the same optimized procedures developed for NIST. Flexible User Interface - Set multiple Desktop configurations with up to seven independently configured windows to examine search results and match your needs. Use with Your Instrument Data Systems - Direct transfer between a number of commercial data systems and the NIST Search Program. Adding User-Drawn Structures
Aids for Automation and Reporting
Automated Mass Spectrometry Deconvolution and Identification System (AMDIS)
The AMDIS software extracts pure component spectra from complex GC/MS or LC/MS data files and searches against specialized libraries or the NIST 05 library. This module was developed at the national Institute of Standards and Technology (NIST) for the critical task of verifying a major international treaty, the Chemical Weapons Convention. After two years of development and extensive testing it is now being made available to the general analytical chemistry community. AMDIS can operate as a "black box" chemical identifier, displaying all identifications that meet a user-selectable degree of confidence. Identification can be aided by internal standards and retention times. Libraries can be built directly from analyzed data files or from spectra in the NIST/EPS/NIH Database. AMDIS can also serve as a preprocessing tool for the GC/MS data files, automatically performing noise reduction for all components. It permits traditional library searching for any selected component. A flexible interface is provided to assist the analysis of complex matrices. Included as a separate utility, AMDIS attempts to reconstruct original mass spectra for individual components in arbitrarily complex GC/MS and LC/MS reconstructed total ion current (RTIC) chromatograms; and, if a target library is provided, can directly identify target compounds. AMDIS is especially useful when an RTIC chromatographic peak represents multiple components. Regardless of each component’s concentration, pure mass spectra are deconvoluted for analyses. AMDIS was developed by NIST for the Defense Weapons Agency (Department of Defense) for verifying compliance with a major international treaty (Chemical Weapons Convention) ratified by the United States Senate in 1997. In order to meet the rigorous requirements for this purpose, AMDIS was tested against more than 30,000 GC/MS data files accumulated by the EPA Contract Laboratory Program without a single false-positive for the target set of known chemical warfare agents. While this level of reliability may not be required for all laboratories, this shows the degree to which the algorithms have been tested. AMDIS has been designed to reconstruct "pure component" spectra from complex RTIC chromatograms even when components are present at trace levels. For this purpose, observed chromatographic behavior is used along with a range of noise-reduction methods. AMDIS is distributed with specialized libraries (environmental, flavor and fragrance, and drugs and toxins), that were derived from the NIST Library. AMDIS has a range of other features, including the ability to search the entire NIST Library with any of the spectra extracted from the original data file. It can also employ retention index windows when identifying target compounds and can make use of internal and external standards maintained in separate libraries. A history list of selected performance standards is also maintained. As of version 2.65, AMDIS reads data files in the following formats:
Additional NIST MS Tools: Mass Spec Interpreter
This utility enables the user to examine neutral losses, isotope patterns and possible chemical formulas along with computer assisted chemical structure/spectral analysis. Starting with Version 1.5, the program has offered a unique means of interpreting spectra of compounds not identified in the Library by the User spectrum search. This is most useful when no acceptable matching spectra are found in a User spectrum search of the NIST Library. At this point, by selecting Substructure Information from the Tools menu, the current hit list is analyzed and statistical information on the composition of the unknown is derived from the hit list. 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.) along with an estimate of the molecular weight and chlorine/bromine content (the latter is based only on the spectrum itself). 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.
New in NIST 08NIST 08 made the following major changes since NIST 05. Electron Ionization (EI) Library: The new library consists of 220,435 spectra of 192,262 compounds an increase of 15% over the previous version. NIST has, at the same time, continued to improve overall library quality by re-measuring and reexamining thousands of spectra. For example, it has been provided consistent identification for hundreds of salts and created a separable collection of low-volatile substances not expected to be measurable by GC/MS (717 spectra of 672 salts). Thousands of spectra of common derivatives and contaminants measured at NIST or by close collaborators have been added. As before, all compounds are represented by both names and chemical structures. GC Data Library: Includes 224,038 Kovacs indices for 21,847 compounds, an increase of over 50% from the previous version. Data include both non-polar and polar columns (NIST 05 had only non-polar columns). Most values were abstracted from the open literature and then compared to replicate values (average of 10 per compound) and estimates to find and remove errors. MS/MS Spectra: This release greatly expands our collection of MS/MS spectra by 250% to 5,308 different precursor ions. A large fraction of the new spectra are for contaminants and metabolites. Some enhancements were also made to the MS Search Software, such as
New in NIST 05NIST 05 made the following major changes since NIST 02. EI Library: This now contains 190,825 spectra of 163,198 different chemical compounds. In addition to the new spectra, important quality improvements have been made in both spectra and compound identification information. The binary format has not changed from the 2002 version, although several new files have been added that associate equivalent compounds and link individual compounds to the retention index library (see below). GC Data: This is a new addition, containing 121,112 Kovats Retention Index values for 25,893 compounds on nonpolar columns, 12,452 of which are compounds represented in the Electron Ionization Library. Full annotation is provided, including literature source and measurement conditions. These are provided in a format accessible by our Search Program. MS/MS Library: This is a new addition, containing 5,191 spectra of 1,943 different ions (1,671 positive and 341 negative ions). Latest new features in the program and database:
New in NIST 02 and previous versionsNIST 02 made the following major changes since NIST 98 and previous versions. The previous version (NIST 98) provided for a 75% increase in coverage and this latest release (NIST 02) provides for an additional 35% increase in coverage. This was accomplished primarily by the addition of complete, high quality spectra either measured specifically for the library or taken from major practical collections, including:
NIST 02 contains spectra of more than 147,000 compounds along with associated chemical identification data including chemical structures, synonyms, and other of relevant information. The best quality spectra are placed in the Main Library; and good-quality, alternate spectra are provided in the Selected Replicates Library, bringing the total number of spectra to about 175,000. This release represents the largest increase in both quality and coverage in the 25-year history of the NIST/EPA/NIH Mass Spectral Database--and for the first time that it can be stated that the library has been fully evaluated. The objective of this effort was to provide the best possible reference library for compound identification by mass spectral library searching. System RequirementsComplete installation (libraries, NIST MS Search program, and AMDIS) requires ~400 MB of free hard disk space. The MS search program requires Windows NT 4.0, Windows 2000, XP, or Vista (instructions are included for two additional installation steps needed to install on Vista). Demo VersionDownload NIST 05 Demo (the software behaves similarly to NIST 08) Note: In order for your MS data system to recognize the demo version, you may need to edit the file "c:\windows\win.ini" (or "c:\winnt\win.ini") to change the line "[NISTMSDEMO]" to "[NISTMS]". Download AMDIS (free) (this is included in demo and need not be downloaded separately) Ordering
Notes on which version to choose (contact us if you have any questions):
Ship Date: NIST 08 is shipping approximately Aug. 1, 2008. Anyone ordering NIST after May 1, 2008 will be shipped the new 2008 version upon release. Additional InformationTIP: Dr. Sparkman at ChemUserWorld has some additional tips on using NIST with Agilent ChemStation, including using separate NIST and Wiley databases on ChemStation.
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