0.4M phosphate buffer ph 6.8 - (Jun/01/2015 )

Hi biologists, 

i am new in biology and would like to know how to prepare 0.4 M phosphate buffer (ph 6.8) i need it to extract hemoglobin and myoglobin from fresh meat. 

thank you for help 

Regards 

you can use a table (like this one or that one) or a calculator (like this one) to determine the proportions of equimolar mono and dibasic phosphate to combine. you can adjust with one or the other to obtain the proper pH without changing the phosphate concentration.

usually you prepare a higher concentration stock and use it to make the final concentration you want with any other additives included.