Calculation of the pH of Buffer Solution of 2-[N -Morpholino]ethanesulfonic Acid (MES) from 5°C to 55°C

Blake M. Bodendorfer, Meagan A. Harmon, Isaac B. Henson, Michael S. Martin, Lakshmi N. Roy, Rabindra N. Roy, Jessica M. Stegner, Joshua T. Wollen

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DOI: 10.4236/ojpc.2011.13011                

Abstract

This paper reports the results for the pH of three buffer solutions free of chloride ion. The remaining six buffer solutions have saline media of the ionic strength I = 0.16 mol.kg^-1, matching closely to that of the physiological sample. Conventional paH values for the three buffer solutions without the chloride ion and six buffer solutions with the chloride ion at I = 0.16 mol.kg^-1 from 5°C to 55°C have been calculated. The operational pH values for five buffer solutions at 5°C and 55°C have been determined based on the difference in the values of the liquid junction potentials between the blood phosphate standard and the experimental buffer solutions. Five of these buffers are recommended as standards for the physiological pH range 7.5 to 8.5.

Keywords

Buffers, MES, BICINE, Liquid Junction, Ionic Strength, Emf, pH

Conflicts of Interest

The authors declare no conflicts of interest.

References

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