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In this section: Laboratory Methods (Food)

BAM R11: Butterfield's Phosphate-Buffered Dilution Water

Reagents Index for BAM

January 2001, February 2013

KH₂PO₄	34 g
Distilled water	500 ml

Adjust pH to 7.2 with 1 N NaOH. Bring volume to 1 liter with distilled water. Sterilize 15 min at 121°C. Store in refrigerator.

Dilution blanks

Take 1.25 ml of above stock solution and bring volume to 1 liter with distilled water. Dispense into bottles to 90 or 99 ± 1 ml. Sterilize 15 min at 121°C.

(Note: This same formulation is referred to as Buffered Dilution Water in American Public Health Association. 1970. Recommended Procedures for the Examination of Seawater and Shellfish, 4th ed. APHA, Washington, DC., p14-15)

Original Source: Bacteriological Analytical Manual, 8th Edition, Revision A, 1998.

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