Preparation of 0.5L of phosphate buffer (pH=6.0)
Alfonso Pérez Escudero, Alid Al-Asmar, gabrielmadirolas
Abstract
Original source of the protocol: WormBook Methods http://www.wormbook.org/chapters/www_strainmaintain/strainmaintain.html
This protocol is for making pH=6.0 phosphate buffer, which is used in the preparation of worm media, like NGM (Nematode Growth Medium).
Steps
Add 54.2g of monopotassium phosphate1 (KH2PO4) to a clean 0.5L bottle.
1Also referred to as potassium phosphate monobasic
Add 17.8g of dipotassium phosphate2 (K2HPO4) to the bottle.
2Also referred to as potassium phosphate dibasic
Measure 500mL of milliQ water in a measuring cylinder, and add it to the bottle.
Shake the bottle vigorously until all crystals are dissolved. This can take a few minutes.
If this is the first time you prepare this solution, you can ensure that the pH is around 6 using pH paper or a pH-meter. We usually have a pH between 5.8 and 6.
Filter-sterilize.
Store on shelf.
We usually use it without problem for at least a year after preparation.
