HDOPP-Ca is a liquid cation exchanger for use in the calcium ion selective electrode. HDOPP is the most suitable compound among the dialkyl phosphate derivatives, and is used in either a liquid membrane or a PVC membrane using DOPP (dioctylphenylphosphate calcium salt) as a plasticizer.
1. J. W. Ross, Calcium-Selective Electrode with Liquid Ion Exchanger. Science. 1967;156:1378-1379.
2. J. Ruzicka, et al., Selectrode – The Universal Ion-selective Electrode Part VI. The Calcium(II) Selectrode Employing a New Ionexchanger in a Nonporous Membrane and a Solid-state Reference System. Anal Chim Acta. 1973;67:155-178.
3. H. M. Brown, et al., A Calcium-sensitive Microelectrode Suitable for Intracellular Measurement of Calcium(II) Activity. Anal Chim Acta. 1976;85:261-276.