Bio-Rad ReadyPrep™ Protein Extraction Kit (Membrane I) User Manual
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Section 4
Instructions for Use
4.1 Membrane Extraction Protocol
Note: Chill buffers M1 and M2 on ice for at least 15 min
before beginning (invert bottles several times during the
incubation).
1. In a microcentrifuge tube, add 0.5 ml of buffer M1 per
25–50 mg of animal tissue or 0.05 ml of wet cell
pellet from sources such as cell culture, yeast, or
bacteria. For plant tissue add 0.5 ml of buffer M1 per
0.25 g. The sample-to-buffer volume ratio indicated
above is only a guide and may be adjusted depending
upon the desired scale of the preparation.
Notes: Protease inhibitors may be added to buffer M1
immediately prior to use to prevent proteolysis during
extraction.
Insufficient volume of buffer M1 may result in poor cell
lysis, low hydrophilic protein yield, and contamination of the
membrane protein fraction with cytoplasmic protei ns.
Plant tissue should be ground to a fine powder using a
mortar and pestle in liquid nitrogen before addition of
buffer M1.
2. Sonicate the suspension on ice with an ultrasonic
probe to break open the cells and fragment the
genomic DNA. During sonication, care must be
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