Changes in apparent pH on freezing aqueous buffer solutions and their relevance to biochemical electron-paramagnetic-resonance spectroscopy

• Published in: Biochemical journal Vol. 167; no. 3; pp. 593 - 600
• Main Authors: Williams-Smith, D L, Bray, R C, Barber, M J, Tsopanakis, A D, Vincent, S P
• Format: Journal Article
• Language: English
• Published: England 01.12.1977
• Subjects: Buffers; Catalase; Copper; Edetic Acid; Electron Spin Resonance Spectroscopy; Freezing; Hydrogen-Ion Concentration; Indicators and Reagents; Nitrate Reductases; Proteins; Xanthine Oxidase

Changes in apparent pH occurring during fast freezing of aqueous buffer solutions and cooling to -196 degrees C were studied by various semiquantitative methods, including simple visual measurements of colour changes with pH indicators, as well as measurements of pH-dependent changes in the e.p.r. (...