Buffer preparation - (Jul/07/2011 )

to prepare the buffer sodium acetate at ph4.5, im instructed to add the acetic acid glacial to lower down the pH level.
I am just wondering that why i could not just use sulphuric acid ?
and if i use sulphuric acid in sodium acetate, it will become sodium bisulfate, and will it give any impact like precipitation when the calcium sulphate is added to it ? any reaction of these two compounds ?
im preparing this buffer to wash the yeast cells, because of handling with cells, am i instructed to use acetic acid glacial instead of sulphuric acid which could be strong for cells or kill them.
please share your knowledge or thoughts if u have any. Thank you.

Acetic acid is an organic acid and is termed "weak" as it forms the CH3COO- form, which has a (relatively) low dissociation constant meaning that not all the H+ is released into solution when acetic acid is added to water. Sulphuric acid is, by contrast, a strong acid meaning that all the H+ ions are released. Adding sulphuric acid to the buffer will also add sulphur in the form of SO4-, which is probably not what you want... stick with the acetic acid until you have enough experience to say what you can fiddle with in the buffer components.