[Comparison of two superparamagnetic purification magnetic beads-based screening and enrichment techniques for isolating cell-free fetal DNA from maternal plasma for non-invasive prenatal screening].

The modified technique to screen and enrich the cffDNA has significantly enhanced the relative concentration of cffDNA and reduced the failure and duplication detection rate of NIPT, which has significantly reduced the incidence of false negative cases due to the low concentration of cffDNA, and greatly increased the overall detection efficacy of NIPT.