NPO RELEASE DOCUMENTS:  To view the new release documents, please go to http://www.nano-ontology.org/documentation/version-release-notes/2011-12-08 
NPO VISUALIZATION: To browse and visualize the NPO, please go to http://purl.bioontology.org/ontology/npo 


  • This version has 72 new classes and 15 new object properties.  
  • Nearly 50 of the new classes describe the different techniques and processes associated with the synthesis of nanomaterials. E.g.,  chemical vapor deposition, micro-emulsion method,  freeze-drying, mixing, etc.
  • New classes have been added under the 'material entity' branch of the ontology, which now has a revised hierarchical structure that is easier to navigate than the previous version.
  • Knowledge about assays and their respective endpoints of measurement can now be represented in the NPO.
Example 1

'size assay' has_endpoint_of_measurement  ('particle size' or 'hydrodynamic size' or 'polydispersity' or 'size')

'particle size' quality_of  'particle'

'partice size'  has_unit_of_measure  ('length unit' or 'area unit' or 'volume unit')


Example 2

'thrombin time assay' has_endpoint_of_measurement 'thrombin time'

'thrombin time' indicator_of 'final common pathway of blood coagulation'

'thrombin time' has_datum value 'time value'

'thrombin time assay' analyze 'final common pathway of blood coagulation'

Note: NPO represents knowledge  of measurable properties by relating terms under the 'quality' and 'realizable entity' branches to terms under  'datum value' and 'unit of measurement' branches of the ontology. 

  • A new relationship is defined for processes that can be associated with  a certain time duration 


'incubation' has_time_period  'duration'

'duration' has_datum_value 'time value'

'time value' has_unit_of_measure 'time unit'

'time value' has_part'  'numeric number'

  • A new relationship is defined for processes that take place at a certain temperature


'incubation' has_temperature_condition 'temperature value'

'temperature value'  measure_of 'temperature'

'temperature value' has_unit_of_measure 'temperature unit'

'temperature value' has_part 'numeric number'

  • The NPO can now support the description and sharing of nanotechnology journal articles



'journal article'  has_Abstract 'string'

'journal article' has_Author 'string'

'journal article' has_DOI 'string'

'journal article' has_Journal_Name 'string'

'journal article' has_PubMedID 'string'

'journal article' has_Publication_Year 'string'

'journal article' has_Title 'string'