How to make ammonium formate buffer. - WKB13629

OBJECTIVE or GOAL

Make ammonium formate buffer for LC runs.

ENVIRONMENT

• LCMS

PROCEDURE

Preparing the mobile phase of 20 mM ammonium formate buffer pH 10

1. Use a 1000-mL graduated cylinder to measure 900 mL of filtered MS-grade water.

2. Use a pipette to add 13.9 mL of the Sigma (28%) ammonium hydroxide solution to the 900 mL of filtered MS-grade water.

3. Mix well.

4. Using a pipette, carefully add 1.62 mL of formic acid to the cylinder.

5. Mix well.

6. Check the pH of the solution. As needed, adjust to pH 10 using the ammonium hydroxide solution or 0.1% formic acid.

7. Add filtered MS-grade water to bring the volume to 1000 mL.

8. Transfer the solution to a 1-L borosilicate bottle and label it "200 mM Ammonium Formate Buffer Stock Solution".

9. Use a 1000-mL graduated cylinder to measure 900 mL of filtered MS-grade water, and then transfer the water to the second 1-L borosilicate bottle.

10. Use a 100-mL graduated cylinder to measure 100 mL of the 200 mM Ammonium Formate Buffer Stock Solution, and then add it to the second borosilicate bottle.

11. Cap the reservoir bottle and mix well.

12. Label the reservoir bottle "20 mM Ammonium Formate Buffer pH 10".

ADDITIONAL INFORMATION