Stock solution A
2 M monobasic sodium phosphate, monohydrate (276g/L)
Stock solution B
2 M dibasic sodium phosphate (284 g/L).
Mixing an appropriate volume (ml) of A and B as shown in the table below and diluting to a total volume of 200 ml, a 1 M phosphate buffer of the required pH at room temperature.
A B pH 92.0 8.0 0.890.0 10.0 5.987.7 12.3 6.085.5 15.0 6.181.5 19.5 6.277.5 22.5 6.373.5 26.5 6.468.5 31.5 6.562.5 37.5 6.656.5 43.5 6.751.0 49.0 6.845.0 55.0 6.939.0 61.0 7.033.0 67.0 7.128.0 72.0 7.223.0 77.0 7.319.0 81.0 7.416.0 84.0 7.5 13.0 87.0 7.610.5 89.5 7.78.5 91.5 7.8