Generation of DNA fragments by sonication
Generation of DNA fragments by sonication is performed by placing a microcentrifuge tube containing the buffered DNA sample into an ice - water bath in a cup - horn sonicator .
Sonication is conducted for a varying number of 10 s bursts using maximum output and continuous power .
Exact conditions for sonication should be empirically determined for a given DNA sample before a preparative sonication is performed .
Typically , 100 µg DNA in TE buffer is split into 10 aliquots of 35 µL .
5 aliquots are subjected to sonication for increasing numbers of 10 s bursts .
Aliquots from each time point are run on an agarose gel to determine optimal - sized DNA fragments ( 1–4 kb ) .
Once optimal sonication conditions are determined , the remaining 5 aliquots ( approximately 8 µg ) are sonicated according to those predetermined conditions .
