Yield and integrity of genomic DNA depend on the disruption and homogenization method used with the Allprep DNA/RNA Kits.
Homogenization with the TissueRuptor (or other rotor–stator homogenizer, such as the Polytron) or the TissueLyser results in greater DNA fragmentation (depending on homogenization time and intensity). However, shorter DNA fragments are easier to elute, so DNA yields will be higher.
In contast, homogenization using the QIAshredder (or a syringe and needle) is more gentle, resulting in less DNA fragmentation. However, longer DNA fragments are more difficult to elute, so DNA yields may be lower.