A-1 Low concentration of cells or virus in the starting sample
—Enrich the concentration of cells or viruses.
A-2 Insufficient lysis of the samples
—The samples has not been mixed thoroughly with the lysis buffer. It is suggested to thoroughly mix by pulse-vortexing for 1-2 times.
—Insufficient cell lysis caused by the activity decrease of proteinase K.
—Insufficient cell lysis or protein degradation due to insufficient warm bath time. It is suggested to cut the tissue into small pieces and extend the bath time to remove all the residue in the lysate.
A-3 Insufficient DNA adsorption.
—No ethanol or low-percentage instead of 100% ethanol was added before the lysate was transfer to the spin column.
A-4 The pH value of elution buffer is too low.
—Adjust the pH to between 8.0-8.3.