Encyclopedia of Metalloproteins

2013 Edition
| Editors: Robert H. Kretsinger, Vladimir N. Uversky, Eugene A. Permyakov

Barium(II) Transport in Potassium(I) and Calcium(II) Membrane Channels

Reference work entry
DOI: https://doi.org/10.1007/978-1-4614-1533-6_170


 Ba;  Barium


Barium is an alkaline earth metal that can be used as a substrate analogue of other alkaline earth metals (e.g., calcium) and alkali metals (e.g., potassium) in electrophysiology and membrane transport researches.


Barium is a chemical element from the group 2 of alkaline earth metals, with symbol Ba and atomic number 56. The name barium originates from Greek barys, meaning “heavy,” and though the chemical has been known for centuries, it was initially isolated in 1808 by the English chemist Sir Humphrey Davy.

Barium is the fourteenth most abundant element in the Earth’s crust and is estimated to constitute about 0.05% of the elemental mass. Nevertheless, Ba is not found in its pure form (a soft silvery-white metal) in nature due to its high reactivity with oxygen and water. The most common naturally occurring barium minerals are barite (barium sulfate, BaSO4) and witherite (barium carbonate, BaCO3).

Physical and Chemical Properties

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Copyright information

© Springer Science+Business Media New York 2013

Authors and Affiliations

  1. 1.Centre for Molecular Medicine Norway (NCMM), Nordic EMBL PartnershipUniversity of OsloOsloNorway