Efficient DNA separation and purification via VIPS-constructed membrane adsorbers

Solid phase extraction is an effective method for the separation and purification of nucleic acid molecules, which still suffers from high loss and low efficiency. Herein, a polyether sulfone membrane adsorber for deoxyribonucleic acid (DNA) separation and purification is constructed by combining vapor-induced phase separation (VIPS) technique and in-situ coupling reaction. More specifically, the slow phase separation during VIPS promotes the formation of reaction platform with loose bicontinuous structure, high porosity and surface segregation of poly (acrylic acid), which is subsequently highly aminated by in-situ coupling of polyethyleneimine. Significantly, the reversible binding of amine ligands to DNA is solely based on electrostatic interaction, which is regulated by medium pH, avoiding the requirement for additional binding agents as encountered by commercial silica matrices and dramatically reducing DNA loss. Consequently, the resulting membrane adsorber exhibits excellent DNA binding capacity of 293.3 mg·g −1 and improved dynamic DNA recovery efficiency of 85.2 %, far exceeding that of commercial silica matrices (55.5 %). This work provides a major breakthrough in the field of nucleic acid separation and purification, paving the way to construct next-generation solid phase extraction materials for biomacromolecules.