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Lidstrom:Buffers: Difference between revisions
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→How does temperature affect the pH of a buffer?
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Amine-containing buffers are most sensitive to changes in temperature. Example: Tris-HCl adjusted to pH=8.0 at 25°C will have a pH of 8.78 at 0°C, whereas carboxylic acid buffers are least sensitive to changes in temperature. Example: acetate buffer adjusted to pH 4.5 at 25°C will have a pH of 4.495 at 0°C. '''These differences are due to the differences in ΔH for ionization of the acids.''' | Amine-containing buffers are most sensitive to changes in temperature. Example: Tris-HCl adjusted to pH=8.0 at 25°C will have a pH of 8.78 at 0°C, whereas carboxylic acid buffers are least sensitive to changes in temperature. Example: acetate buffer adjusted to pH 4.5 at 25°C will have a pH of 4.495 at 0°C. '''These differences are due to the differences in ΔH for ionization of the acids.''' | ||
(source: [http://www.amazon.com/Enzyme-Assays-Practical-Approach-Series/dp/0199631425/ref=sr_1_1?ie=UTF8&qid=1383921457&sr=8-1&keywords=0199631425 ISBN 0-19-963142-5] pg | (source: [http://www.amazon.com/Enzyme-Assays-Practical-Approach-Series/dp/0199631425/ref=sr_1_1?ie=UTF8&qid=1383921457&sr=8-1&keywords=0199631425 ISBN 0-19-963142-5] pg 319) | ||
=== How do method developer chose between sodium and potassium phospahte buffers? === | === How do method developer chose between sodium and potassium phospahte buffers? === | ||
