, Volume 15, Issue 3, pp 237–249 | Cite as

Determination of [Mg2+]i – an update on the use of Mg2+-selective electrodes

  • Dorothee Günzel
  • Wolf-Rüdiger Schlue


Since their invention, ion-selective microelectrodes have become an indispensable tool for investigations of intracellular ion regulation and transport. While highly selective sensors for all major intracellular monovalent ions have been available for decades, the development of sensors for divalent cations seems to have presented more difficulties. As ion-selective microelectrodes typically have time-constants in the range of 0.5 to several seconds they turned out to be inapt for the investigation of intracellular Ca2+. The development of sensors for Mg2+-selective electrodes has made its most striking progress only over the past few years. While the first Mg2+ sensor, ETH 1117, was barely able to detect physiological Mg2+ concentrations in the presence of other mono- and divalent cations, the newest sensors allow measurements in the micromolar range. When used in macroelectrodes, the most recent developments, ETH 5506 and ETH 5504, have even been reported to do so in the presence of millimolar Ca2+ concentrations. Although there is still room for improvement to make these sensors applicable in microelectrodes, some preliminary data look extremely promising and indicate that a new era for Mg2+-selective microelectrodes is about to start.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Ammann D. 1986 Ion-Selective Microelectrodes. Principles, Design and Application. Berlin: Springer Verlag.Google Scholar
  2. Alvarez-Leefmans FJ, Gamiño SM, Rink TJ. 1984 Intracellular free magnesium in neurones of Helix aspersa measured with ion-selective micro-electrodes. J Physiol (Lond) 354, 303-317.Google Scholar
  3. Alvarez-Leefmans FJ, Gamiño SM, Giraldez F, González-Serratos H. 1986 Intracellular free magnesium in frog skeletal muscle fibres measured with ion-selective micro-electrodes. J Physiol (Lond) 378, 461-483.Google Scholar
  4. Alvarez-Leefmans FJ, Giraldez F, Gamiño SM 1987 Intracellular free magnesium in excitable cells: its measurement and its biologic significance. Can J Physiol Pharmacol 65, 915-925.Google Scholar
  5. Blatter LA, McGuigan JAS. 1986 Free intracellular magnesium concentration in ferret ventricular muscle measured with ion selective micro-electrodes. Quart J Exp Physiol 71, 467-473.Google Scholar
  6. Blatter LA, McGuigan JAS. 1988 Estimation of the upper limit of the free magnesium concentration measured with Mg-sensitive microelectrodes in ferret ventricular muscle: (1) use of the Nicolsky-Eisenman Equation and (2) in calibration solutions of the appropriate concentration. Magnesium 7, 154-165.Google Scholar
  7. Borrelli MJ, Carlini WG, Dewey WC, Ransom BR. 1985 A simple method for making ion-selective microelectrodes suitable for intracellular recording in vertebrate cells. J. Neurosci. Meth. 15, 141-154.Google Scholar
  8. Buri A, Chen S, Fry CH, Illner H, Kickenweiz E, McGuigan JAS, Noble D, Powell T, Twist VW. 1993 The regulation of intracellular Mg2+ in guinea-pig heart, studied with Mg2+-selective microelectrodes and fluorochromes. Exp Physiol 78, 221-233.Google Scholar
  9. Buri A, McGuigan JAS. 1990 Intracellular free magnesium and its regulation, studied in isolated ferret ventricular muscle with ion-selective microelectrodes. Exp Physiol 75, 751-761.Google Scholar
  10. Caldwell PC. 1954 An investigation of the intracellular pH of crab muscle fibres by means of micro-glass and micro-tungsten electrodes. J Physiol (Lond) 126, 169-180.Google Scholar
  11. Coles JA, Tsacopoulos M. 1977 A method of making fine double-barrelled potassium-sensitive micro-electrodes for intracellular recording. J Physiol (Lond) 270, 13-14P.Google Scholar
  12. Gasser RNA. 1990 A microelectrode study of the mechanisms of ionic and electrical changes during simulated ischaemia in isolated cardiac muscle. D. Phil. Thesis, Oxford.Google Scholar
  13. Günther T, Vormann J, McGuigan JAS. 1995 Buffering and activity coefficient of intracellular free magnesium concentration in human erythrocytes. Biochem. Molec. Biol. Int. 37, 871-875.Google Scholar
  14. Günzel D, Galler S. 1991 Intracellular free Mg2+ concentration in skeletal muscle fibres of frog and crayfish. Pflügers Arch 417, 446-453.Google Scholar
  15. Günzel D, Schlue W-R. 1996 Sodium / magnesium antiport in Retzius neurones of the leech Hirudo medicinalis. J Physiol (Lond) 491, 595-608.Google Scholar
  16. Günzel D, Schlue W-R. 1997 Interactions between magnesium, sodium and intracellular pH in leech Retzius neurones. In: Smetana R., ed. Advances in Magnesium Research. London: John Libbey; 497-506.Google Scholar
  17. Günzel D, Schlue W-R. 2000 Mechanisms of Mg2+ influx, efflux and intracellular 'muffling' in leech neurones and glial cells. Magnes Res. 13, 123-138.Google Scholar
  18. Günzel D, Durry S, Schlue W-R. 1997 Intracellular alkalinization causes Mg2+ release from intracellular binding sites in leech Retzius neurones. Pflügers Arch 435, 65-73.Google Scholar
  19. Günzel D, Müller A, Durry S, Schlue W-R. 1999 Multi-barrelled ion-sensitive microelectrodes and their application in microdroplets and biological systems. Electrochim. Acta 44, 3785-3793.Google Scholar
  20. Günzel D, Zimmermann F, Durry S, Schlue W-R. 2001 Apparent intracellular Mg2+ buffering in neurones of the leech Hirudo medicinalis. Biophys J 80, 1298-1310.Google Scholar
  21. Fry CH, Hall SK, Blatter LA, McGuigan JAS. 1990 Analysis and presentation of intracellular measurements obtained with ion-selective microelectrodes. Exp Physiol 75, 187-198.Google Scholar
  22. Hess P, Metzger P, Weingart R. 1982 Free magnesium in sheep, ferret and frog striated muscle at rest measured with ion-selective micro-electrodes. J Physiol (Lond) 333, 173-188.Google Scholar
  23. Hintz K, Günzel D, Schlue W-R. 1999 Na+-dependent regulation of the free Mg2+ concentration in neuropile glial cells and P neurones of the leech Hirudo medicinalis. Pflügers Arch 437, 345-362.Google Scholar
  24. Horlitz M, Klaff P. 2000 Gene-specific trans-regulatory functions of magnesium for chloroplast mRNA stability in higher plants. J Biol Chem 275, 35638-35645.Google Scholar
  25. Hu Z, Bührer T, Müller M, Rusterholz B, Rouilly M, Simon W. 1989 Intracellular magnesium ion selective microelectrode based on a neutral carrier. Anal Chem 61, 574-576.Google Scholar
  26. Kennedy HJ. 1998 Intracellular Mg2+ regulation in voltage-clamped Helix aspersa neurones measured with mag-fura-2 and Mg2+-sensitive microelectrodes. Exp Physiol 83, 449-460.Google Scholar
  27. Lanter F, Erne D, Ammann D, Simon W. 1980 Neutral carrier based ion-selective electrode for intracellular magnesium activity studies. Anal Chem 52, 2400-2402.Google Scholar
  28. Lopez JR, Alamo L, Caputo C, Vergara J, DiPolo R. 1984 Direct measurement of intracellular free magnesium in frog skeletal muscle using magnesium-selective microelectrodes. Biochim Biophys Acta 804, 1-7.Google Scholar
  29. Lüthi D, Spichiger U, Forster I, McGuigan JAS. 1997 Calibration of Mg2+-selective macroelectrodes down to 1 µmol lμ1 in intracellular and Ca2+-containing extracellular solutions. Exp Physiol 82, 453-467.Google Scholar
  30. Lüthi D, Günzel D, McGuigan JAS. 1999 Mg-ATP binding: its modification by spermine, the relevance to cytosolic Mg2+ buffering, changes in the intracellular ionized Mg2+ concentration and the estimation of Mg2+ by 31P-NMR. Exp Physiol 84, 231-252.Google Scholar
  31. MacDermott M. 1990 The intracellular concentration of free magnesium in extensor digitorum longus muscles of the rat. Exp Physiol 75, 763-769.Google Scholar
  32. Marsoner HJ, Spichiger UE, Ritter C, Sachs C, Ghahramani M, Offenbacher H, Kroneis H, Kindermans C, Dechaux M. 1994 Measurement of ionized magnesium with neutral carrier based ISE's. Progress and results with the AVL 988-4 magnesium analyzer. Scand J Clin Lab Invest 54 (Suppl. 217), 45-51.Google Scholar
  33. McGuigan JAS, Blatter LA. 1989 Measurement of free magnesium using magnesium selective microelectrodes. Magnesium-Bull. 11, 139-142.Google Scholar
  34. McGuigan JAS, Blatter LA, Buri A. 1990 Use of ion selective microelectrodes to measure intracellular free Mg2+. In: Strada P, Carbone E, ed. Mg 2+ and Excitable Membranes. Berlin: Springer-Verlag.Google Scholar
  35. McGuigan JAS, Buri A, Chen S, Illner H, Lüthi D. 1993 Some theoretical and practical aspects of the measurement of the intracellular free magnesium concentration in heart muscle: Consideration of its regulation and modulation. In: Birch NJ, ed. Magnesium and the Cell. London: Academic Press.Google Scholar
  36. Mooren FC, Turi S, Günzel D, Schlue W-R, Domschke W, Singh J, Lerch MM. 2001 Calcium-magnesium interactions in pancreatic acinar cells. FASEB J. 15, 659-672Google Scholar
  37. Müller A, Günzel D, Schlue W-R. 1997a Stoichiometry of sodium/magnesium antiport in leech Retzius neurones. In: Smetana R, Advances in Magnesium Research. London: John Libbey; 507-513.Google Scholar
  38. Müller A, Günzel D, Schlue W-R. 1997b Effect of kainate on [Mg2+]i, [Na+]i, pHi and Em in leech Retzius neurones. Magnes-Bull 19, 128.Google Scholar
  39. Munoz J-L, Deyhimi F, Coles JA. 1983 Silanization of glass in the making of ion-sensitive microelectrodes. J Neurosci Moth 8, 231-247.Google Scholar
  40. Munsch T, Reinhard C, Deitmer JW. 1995 Die intrazelluläre Magnesium-Konzentration identifizierter Neurone und Gliazellen aus dem Zentralnervensystem des Blutegels. Proc German Zool Soc 88, 11.Google Scholar
  41. O'Donell J, Li HB, Rusterholz B, Pedrazza U, Simon W. 1993 Development of magnesium-selective ionophores. Anal Chim Acta 281, 129-134.Google Scholar
  42. Orme FW. 1969 Liquid ion-exchanger microelectrodes. In: Lavallée M, Schanne OF, Hebert NC, eds. Glass Microelectrodes. New York: John Wiley & Sons, Inc.Google Scholar
  43. Rönnau K. 1984 A simplified method for silanization of double-barrelled ion-sensitive microelectrodes. Experientia 40, 1019-1020.Google Scholar
  44. Schaller U, Spichiger UE, Simon W. 1993 Novel magnesium ion-selective microelectrodes based on a neutral carrier. Pflügers Arch 423, 338-342.Google Scholar
  45. Spichiger UE, Fakler A. 1997 Potentiometric microelectrodes as sensors and detectors. Magnesium-selective electrodes as sensors, and Hofmeister electrodes as detectors for histamine in capillary electrophoresis. Electrochim Acta 42, 3137-3145.Google Scholar
  46. Thomas RC. 1978 Ion-Sensitive Intracellular Microelectrodes. How to Make and Use Them. London: Academic Press.Google Scholar
  47. Tsien RY, Rink TJ. 1981 Neutral carrier ion-selective microelectrodes for measurement of intracellular free calcium. Biochim Biophys Acta 599, 623-638.Google Scholar
  48. Walker JL. 1971 Ion specific liquid ion exchanger microelectrodes. Anal Chem 43(3), 89A-92A.Google Scholar
  49. Zhang W, Truttmann AC, Lüthi D, McGuigan JAS. 1995 The manufacture and characteristics of magnesium selective macroelectrodes. Magnes-Bull. 17, 125-130.Google Scholar
  50. Zhang W, Truttmann AC, Lüthi D, McGuigan JAS. 1997 Apparent Mg2+-adenosine 5-triphosphate dissociation constant measured with Mg2+ macroelectrodes under conditions pertinent to 31P NMR ionized magnesium determinations. Anal Biochem 251, 246-250.Google Scholar
  51. Zhang W, Fakler A, Demuth C, Spichiger UE. 1998 Comparison of different methods for determining the selectivity coefficient using a magnesium-selective electrode. Anal Chim Acta 375, 211-222.Google Scholar
  52. Zhang X, Fakler A, Spichiger UE. 1998 Development of magnesium-ion-selective microelectrodes based on a new neutral carrier ETHT 5504. Electroanalysis 10, 1174-1181.Google Scholar

Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • Dorothee Günzel
    • 1
  • Wolf-Rüdiger Schlue
    • 1
  1. 1.Institut für NeurobiologieHeinrich-Heine-Universität DüsseldorfDüsseldorfGermany

Personalised recommendations