vocabulary:
  name: Sigma-Aldrich Life Science Vocabulary
  description: >-
    Domain vocabulary for the Sigma-Aldrich research chemical and biochemical
    catalog, covering chemical identification, product classification, safety
    regulations, and life science research concepts.
  version: '1.0'
  created: '2026-05-02'
  provider: Sigma-Aldrich (MilliporeSigma)

terms:
  - term: CAS Number
    definition: >-
      Chemical Abstracts Service Registry Number — a unique numeric identifier
      assigned to every chemical substance described in the literature by the
      American Chemical Society's Chemical Abstracts Service. Format is
      xxxxxxx-yy-z (up to 7 digits, 2 digits, 1 check digit). Used globally
      as the definitive identifier for chemical compounds.
    synonyms:
      - CAS RN
      - CAS Registry Number
    examples:
      - '7732-18-5: Water (H2O)'
      - '64-17-5: Ethanol'
      - '7647-14-5: Sodium Chloride'

  - term: SMILES
    definition: >-
      Simplified Molecular Input Line Entry System — a notation that allows
      a user to represent a chemical structure in a way that can be used
      by a computer, using ASCII characters to encode atoms, bonds, and
      connectivity. Used for structure search and cheminformatics workflows.
    synonyms:
      - Simplified Molecular Input Line Entry System

  - term: InChI
    definition: >-
      IUPAC International Chemical Identifier — a textual identifier for
      chemical substances that encodes the molecular structure in a
      standardized format. The InChIKey is a hashed 27-character version
      used for database indexing and web searches.
    synonyms:
      - International Chemical Identifier

  - term: Safety Data Sheet (SDS)
    definition: >-
      A standardized document providing health and safety information about
      a chemical substance or mixture, required by GHS (Globally Harmonized
      System) regulations. Contains 16 mandatory sections including hazard
      identification, composition, first aid, handling, and storage.
      Formerly called Material Safety Data Sheet (MSDS).
    synonyms:
      - SDS
      - MSDS
      - Material Safety Data Sheet
    related:
      - GHS
      - REACH

  - term: GHS
    definition: >-
      Globally Harmonized System of Classification and Labelling of Chemicals
      — a United Nations system for standardizing chemical hazard communication
      worldwide through uniform SDS formats and hazard pictograms.
    synonyms:
      - Globally Harmonized System

  - term: Molecular Weight
    definition: >-
      The mass of one molecule of a chemical substance, expressed in grams
      per mole (g/mol) or unified atomic mass units (u). Calculated as the
      sum of atomic masses of all atoms in the molecular formula.
    synonyms:
      - molar mass
      - formula weight
    unit: g/mol

  - term: Purity
    definition: >-
      The percentage of the target compound in a chemical sample, with the
      remainder being other chemicals or impurities. Sigma-Aldrich uses grades
      such as ≥99.0%, ≥99.5%, ACS reagent, BioReagent, and HPLC grade to
      indicate purity and suitability for different applications.
    related:
      - Grade

  - term: Grade
    definition: >-
      A classification indicating the quality and intended application of
      a chemical product. Common Sigma-Aldrich grades include ACS reagent
      (meets American Chemical Society purity standards), BioReagent (for
      biological research), HPLC Plus (high purity for chromatography),
      ReagentPlus (≥99% purity), and BioXtra (extra purity for biological use).
    values:
      - ACS reagent
      - BioReagent
      - HPLC Plus
      - ReagentPlus
      - BioXtra
      - Technical grade
      - Pharmaceutical grade

  - term: Substructure Search
    definition: >-
      A chemical structure search mode that finds all compounds in a database
      that contain the query structure as a subgraph of their molecular graph.
      Used to find analogs and members of chemical classes in drug discovery
      and materials science.
    synonyms:
      - SSS
      - substructure query

  - term: Similarity Search
    definition: >-
      A chemical structure search mode that ranks compounds by their
      structural similarity to a query molecule using fingerprint-based
      algorithms such as Tanimoto coefficient. Allows configuring a
      similarity threshold to control result set breadth.
    synonyms:
      - Tanimoto search
      - fingerprint similarity

tags:
  - Life Science
  - Chemistry
  - Biochemistry
  - Cheminformatics
  - Laboratory
  - Research
  - GHS
  - Safety
  - Drug Discovery
  - Materials Science