Nanoplastics Alter DNA

Here we show that the direct binding of functionalized polystyrene chains can trigger biochemically relevant structural changes in DNA helices. For the stable association of the plastic and the biomolecule, the presence of the positively charged functional groups was found to be essential, which form strong Coulombic interactions with the phosphate moieties of the DNA, overcoming the interplay between the biomolecule and the aqueous medium. The geometric features of DNA showed a distinct shift from the initial B-DNA structure to the A-DNA form through the 100 ns simulations, implying that in the presence of the plastic the latter, rarer form becomes preferred. These conformational changes can have significant biochemical consequences and may be a part of the toxic effect of these materials.