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pH and Buffers

  1. Irwin H Segel,
  2. Leigh D Segel

Published Online: 21 AUG 2001

DOI: 10.1038/npg.els.0003117



How to Cite

Segel, I. H. and Segel, L. D. 2001. pH and Buffers. eLS. .

Author Information

  1. University of California at Davis, California, USA

Publication History

  1. Published Online: 21 AUG 2001


Many biomolecules possess weakly acidic or weakly basic groups whose ionization state can affect both biological function and stability, and many biological processes, such as oxidation–reduction reactions, produce or consume hydrogen ions. The extents of the reactions and the rates at which they proceed depend on the acidity of the reaction environment. Buffers are used to maintain a constant hydrogen ion activity.


  • weak acid;
  • weak base;
  • pH;
  • buffer;
  • temperature;
  • ionic strength