buffer used in experiments?

Question

why the buffer used must be isotonic and cold in experiments?

Answer 1

a buffer is needed in experiments to maintain a constant pH throughout a reaction and isotonic means that it must be the same as the surrounding (the word isotonic means medically that the eye drops must be isotonic to the eye fluid meaning that he same concentration of salts in both are equal) hope this helped!!

Answer 2

Also temp decreases enzyme activity, so preserves more stuff (post translational modifications for example)