A novel method for absolute calibration of intracellular pH indicators (original) (raw)

Abstract

In this paper we present methods to measure intracellular pH (pHi) with fluorescent indicators. These methods are based on the change in intracellular pH following the addition of weak acids and weak bases to the extracellular medium. The first method requires that the fluorescence of the indicator is proportional to the change in pHi that follows the addition of a weak acid or weak base to the extracellular medium. The second is a null method which uses a mixture of weak acid and weak base that does not change the fluorescent signal. This null method can be used in situations in which the fluorescent signal is a monotonic but non-linear function of pH. The first method depends upon four assumptions. (i) That only the uncharged forms of the weak acids and bases cross the surface membrane. (ii) That the pKa is the same inside and outside the cell. (iii) That the buffering power is constant. (iv) That there is no significant pH regulation on the time scale of the change in pHi. The null method only requires the first two assumptions. We have made estimates of pHi in four different cell types and compared the results obtained with these methods with those obtained from other methods of pHi calibration.

Access this article

Log in via an institution

Subscribe and save

Buy Now

Price excludes VAT (USA)
Tax calculation will be finalised during checkout.

Instant access to the full article PDF.

Similar content being viewed by others

References

Download references

Author information

Authors and Affiliations

  1. Department of Physiology, University College London, Gower St, WC1E 6BT, London, UK
    D. A. Eisner, S. C. O'Neill & M. Valdeolmillos
  2. Department of Physiology, Royal Free Hospital School of Medicine, Rowland Hill St, NW3 2PF, London, UK
    N. A. Kenning, G. Pocock & C. D. Richards

Authors

  1. D. A. Eisner
    You can also search for this author inPubMed Google Scholar
  2. N. A. Kenning
    You can also search for this author inPubMed Google Scholar
  3. S. C. O'Neill
    You can also search for this author inPubMed Google Scholar
  4. G. Pocock
    You can also search for this author inPubMed Google Scholar
  5. C. D. Richards
    You can also search for this author inPubMed Google Scholar
  6. M. Valdeolmillos
    You can also search for this author inPubMed Google Scholar

Rights and permissions

About this article

Cite this article

Eisner, D.A., Kenning, N.A., O'Neill, S.C. et al. A novel method for absolute calibration of intracellular pH indicators.Pflugers Arch. 413, 553–558 (1989). https://doi.org/10.1007/BF00594188

Download citation

Key words