I am working with Sera-Mag paramagentic beads to isolate whole genomic DNA from human fibroblasts.

I follow the general protocol: bind DNA to beads with PEG/NaCl solution, place on magnetic rack, wash with 70% ethanol, dry, elute with 10mM Tris-HCl (T10).

However, I am having a great deal of trouble eluting. The beads stick to the DNA so tightly that I cannot dissociate the beads to release the gDNA. It looks like a pellet floating inside the T10. I flick the tube as much as possible, but when I put the tube back on the rack to collect the elute, I can see that the beads are still puffy with gDNA (meaning the gDNA is not in solution). 

I have tried incubating at 37C for various lengths of time (minutes to days). I have also tried doing a phenol/chloroform extraction first in order to get rid of protein (from cell lysis) that can interfere with the beads. Yet I still encounter this elution issue. 

My thought is that the whole gDNA is so long that it is wrapping around the beads and entangling them. However, I need to keep the DNA whole. I do not want to fragment it before using Sera-Mag beads. 

Any suggestions would be appreciated. 

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