Calcium Chelation and Buffers

  • P. C. Caldwell
Part of the Biological Council book series


An approach which has proved very useful in studies of the role of calcium in biological systems, in particular in muscle, is the use of substances which selectively bind this ion. One of the best known compounds of this type is ethylene-diamine-tetra-acetic acid (EDTA) which binds calcium about 100 times more effectively than it binds magnesium. In recent years, however, EDTA has been superseded in many studies involving calcium by ethylene-glycol bis (β-amino-ethyl-ether)-N,N′-tetra-acetic acid (EGTA) which can bind calcium over 105 times more effectively than it binds magnesium. This article is concerned with some of the uses which have been made of EGTA in studying the role of calcium in the contraction of the large single muscle fibres which can be obtained from certain crustacea, in particular crabs (Maia squinado) and barnacles (Balanus nubilus).


Association Constant Contractile Response Ionize Calcium Concentration Calcium Chelation Single Muscle Fibre 


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Copyright information

© Palgrave Macmillan, a division of Macmillan Publishers Limited 1970

Authors and Affiliations

  • P. C. Caldwell
    • 1
  1. 1.Department of ZoologyUniversity of BristolEngland

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