Focusing on dissolution studies of drugs, if a buffer was made with a pH of 6.8 with a temperature of 25'C and than transferred to a Vessel of whose the temperature is 37'C, won't the buffering capacity change?
If yes, can we calculate the change?
Hello Jimon Parashar I would say YES but maybe it is not a significative change, let´s say from 6.8 to 6.7. It will always decrease its pH since acids tend to dissociate more at higher temperatures. If you know the pka of your acid at 37 °C, you can calculate the new value. But why don´t you get your buffer, put it into a water bath at 37 °C, and take it to a pHmeter? It could also answer your question.
Good luck!
You may want to check also this RG thread:
https://www.researchgate.net/post/Why-does-the-PH-of-tris-base-buffer-change-with-temperature-variation
In addition to Leonardo's answer you can check how the pka values for several common buffers change from 25 to 37 °C via the following link and/or the attached document.
https://www.sigmaaldrich.com/DE/de/technical-documents/protocol/protein-biology/protein-concentration-and-buffer-exchange/buffer-reference-center#selected-buffers
In most cases, the changes in pH won't be dramatic, but it is always advisable to prepare your buffers at the same temperature you will be using in the assay.
Best regards.
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