Q1: My lysate seems viscous. What is causing this to happen? How can I fix this?
A viscous sample can indicate incomplete sample lysis. Try using less of your sample and optimize bead beating conditions (duration, speed, time) to ensure samples are thoroughly lysed. After bead beating, pellet the cell debris before moving on. Adding more Genomic Lysis buffer to the lysate can help dilute and deproteinate the sample, making the sample less viscous and more suitable for DNA recovery.
Q2: Is it necessary to add beta-mercaptoethanol? Can this step be substituted or omitted?
Addition of beta-mercaptoethanol is recommended to enhance sample lysis, but can be substituted with dithiothreitol (DTT, final concentration of 10 mM). However, if bead beating is optimized and lysis is efficient, the addition of BME is not necessary and can be omitted.
Q3: When can an RNase A treatment be implemented in the protocol?
No additional RNase A treatment is required when processing samples within kit capacity. The selective chemistry allows for binding of double stranded DNA to the column and for RNA to flow through.