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Products Search Guide

The Product Search allows searching for all Sigma-Aldrich brands. You may search the Full Text of the catalog, or limit your search scope to certain fields: Product Number, Product Name, CAS Number, MDL number, or Molecular Formula.

Product Name
Product Number
CAS Number
Product Identifier
Molecular Formula
Full Text

Product Name - by searching product names, your hit list will not include products that may mention other substances (e.g., as solvent, buffer component, substrate, etc.) in their listings.
Example: By searching for sodium AND chloride under "Full Text Search" you would find hundreds of products that were prepared or stored with sodium chloride. By searching under "Product Name" you will limit your search to those products where Sodium and Chloride are in the Product Name field.

NOTE: When doing name searches it is best to leave out the numbers, Greeks, and single letters that serve as locants, as well as all the punctuation.

Product Number - most straightforward of the searching options, searches strictly product numbers.

NOTE: Do not use punctuation when entering product numbers. i.e. Enter T1503, NOT T-1503.

The Product Number Search is an "exact match" search, not "starts with" or "contains".

CAS (Chemical Abstract Service) Number - these registry numbers are assigned by independent organizations to unambiguously refer to specific substances. The numbers vary in how specifically they define the substance. We make every effort to provide the most correct CAS number which applies. CAS does not assign registry numbers to mixtures or solutions. In such cases, we provide the CAS number of the solute or component referred to in the main name.

NOTE: you may use the normal hyphenation or leave the hyphens out when entering CAS numbers for searching.

The CAS Number Search is an "exact match" search, not "starts with" or "contains".

Product Identifier - allows you the option to search by a number of common industry identifiers. MDL No., Enzyme Commission No., Colour Index No., Beilstein No., and FEMA No..

The Product Identifier Search is an "exact match" search, not "starts with" or "contains".

Molecular Formula - enter each atomic symbol followed by the number of those atoms without spaces. Don't try to enter as a subscript. For example, 4-chlorobenzoic acid would be C7H5ClO2. Be careful with the zeroes and the ohs.

NOTE: formulas must be entered with strict Hill system compliance: carbon first, hydrogen next, then all other elements in alphabetical order of their symbols. Ammonium carbonate should be CH8N2O3.

The Molecular Formula Search is an "exact match" search, not "starts with" or "contains".

Full Text - allows you to search the entire text of the catalog, including full product descriptions. You are unlikely to miss anything of interest with a full text search, but your hit list may be extremely long.

The search program also allows for complex text searching procedures including "weighting" the words to preserve order of entry, Boolean logic and wildcards. The Full Text Search can either be an "and", "or", or "not" search.