Size distribution of cfDNA. Matched cfDNA samples isolated from CTC-depl. blood ( B , D ; CTC isolation using AdnaTest EMT-2/StemCell Select) and from whole blood ( A , C ) of two exemplary patients ( A + B ; C + D ) displayed a large mononucleosomal fraction and, in general, a similar size distribution without high-molecular-weight DNA (700–10,000 bp). Capillary electrophoresis was performed with an Agilent High Sensitivity Chip. (A) Cell-free DNA eluate from whole blood of patient 2, diluted 1:40; ( B ) cfDNA eluate from CTC-depl. blood of patient 2, diluted 1:40; ( C ) cfDNA eluate from whole blood of patient 3, diluted 1:5; (D) cfDNA eluate from CTC-depl. blood of patient 3, diluted 1:20.