I am currently performing cell-free DNA (cfDNA) extraction from plasma using an in-house developed kit that employs silica-coated magnetic beads. My protocol works effectively with plasma obtained from blood bank donations, which is collected and stored in CPD SAGM bags at -80°C. However, I face issues when using plasma separated from blood collected in K2 EDTA tubes. Could anyone shed light on why my cfDNA extraction might be failing with plasma from EDTA vacutainers? Any insights or suggestions for protocol adjustments would be greatly appreciated.