I regularly purify cell free DNA from patient plasma samples using Qiamp circulating nucleic acid kit, followed by analysis on BioAnalyzer which indicates genomic DNA contamination in few of the samples. I am looking for the protocols to purify cell free DNA from those samples by size selection. I have been thinking to use Ampure XP beads for the same. If anyone has used the same for similar purpose, it will be very helpful, if you can share your protocols with me.
Or you can suggests any other kit available for size selection of DNA below 200 bp, please let me know.