Composite material of DNA and cyclodextrin-immobilized poly(ethyleneimine): Accumulation of harmful compounds from multi-component solution

Water-soluble β-cyclodextrin-immobilized poly(ethyleneimine) (PEICD) was synthesized by the grafting of β-cyclodextrin to the branched poly(ethyleneimine). In an aqueous solution, this PEICD polymer could encapsulate bisphenol A, known to be a harmful compound. Additionally, the stability constant of bisphenol A to the PEICD polymer was 1.1 × 104 M−1. However, the water-solubility of PEICD has been making it difficult to utilize it as an environmental material. Therefore, we prepared the DNA–PEICD composite material by mixing the double-stranded DNA and PEICD. This DNA–PEICD composite material was extremely stable in water and possessed both properties of the intercalation into the double-stranded DNA and the encapsulation into the CD cavity. As a result, this material can accumulate various harmful compounds, such as dioxin- and polychlorobiphenyl (PCB)-derivatives and bisphenol A, from a multi-component solution. Therefore, the DNA–PEICD composite material may have the potential to be used as an environmental material.