Complete Lysis-M Buffer from Roche comes in a kit that includes 200 mL of EDTA-free lysis buffer and 20 protease inhibitor tablets. The kit should be stored at room temperature. To use, one tablet is dissolved in 10 mL of lysis buffer for approximately 2 minutes. The solution is then vortexed briefly to ensure distribution of the tablet.
Roche states that the Complete Lysis–M buffer provides a higher protein yield as compared to sonication and free-thaw extraction methods. Because the buffer contains no EDTA, any metalloproteases present in the sample are unaffected. The kit does not contain phosphatase inhibitors so those must be purchased separately and added, if desired.
I used the Complete Lysis-M Buffer for lysis of adherent mammalian cancer cells. I grew the cells in a 150 mm tissue culture plate until confluent. After placing the plate on ice, I removed the media and washed once with Phosphate Buffered Saline (PBS). I then added 1mL of Complete Lysis-M buffer to the plate and scraped the cells and transferred them to a microcentrifuge tube. I left the sample on ice for thirty minutes after which I centrifuged for 15 minutes at 4 degrees at 14,000xg to separate the cell debris from the protein. Then I transferred the supernatant to a new microcentrifuge tube and measured the protein concentration using a BCA assay. My lysates were later used for Western blotting.
I found the Complete Lysis-M Buffer to provide a fast and efficient lysis. Overall, the instructions were easy to follow and the buffer was simple to mix. Roche provides detailed tables with suggest volumes of lysis buffer to use. Protocols are also provided for lysis of suspension cells. The kit is reasonably priced and can be used for approximately 100 g of cells. I am satisfied with the outcome of the complete Lysis-M Buffer and will continue to use it.