Kamaishu Biotechnology Today's Technical Recommendation - Preparation Method of Phosphate Buffer

Phosphate Buffer (PB)
Reagents: NaH2PO4·2H2O Na2HPO4·12H2O
Preparation method: When preparing, always prepare 0.2mol/L NaH2PO4 and 0.2mol/L Na2HPO4, and mix them in a certain ratio to form 0.2mol/L phosphate buffer (PB), and prepare different concentrations as needed. PB and PBS.
(1) 0.2 mol/L of Na2HPO4; Na2HPO4.12H2O 31.2 g (or NaH2PO4·H2O 27.6 g) was weighed and distilled water was added to 1000 ml to dissolve.
(2) 0.2 mol/L of Na2HPO4: NaHPO4.12H2O 71.632 g (or Na2HPO4·7H2O 53.6 g or Na2HPO4·2H2O 35.6 g) was weighed and the distilled water was added to 1000 ml to dissolve.
(3) Preparation of 0.2 mol/L PB of pH 7.4: Take 19 ml of 0.2 mol/L NaH2PO4 and 81 ml of 0.2 mol/L of Na2HPO4·12H2O, and mix well to be 0.2 mol/L of PB (pH is about 7.4~) 7.5). If the pH is high or low, it can be adjusted by changing the ratio of the two, and it can be stored at room temperature.
0.2mol/L phosphate buffer (pH 5.7 ~ 8.0)
pH 0.2mol/L NaH2PO4(ml) 0.2mol/L Na2HPO4(ml)
5.7 93.5 6.5
5.8 92.0 8.0
5.9 90.0 10.0
6.0 87.7 12.3
6.1 85.0 15.0
6.2 81.5 18.5
6.3 77.5 22.5
6.4 73.5 26.5
6.5 68.5 31.5
6.6 62.5 37.5
6.7 56.5 43.5
6.8 51.0 49.0
6.9 45.0 55.0
7.0 39.0 61.0
7.1 33.0 67.0
7.2 28.0 72.0
7.3 23.0 67.0
7.4 19.0 81.0
7.5 16.0 84.0
7.6 13.0 87.0
7.7 10.5 89.5
7.8 8.5 91.5
7.9 7.0 93.0
8.0 5.3 94.7