Novel polymeric ionic liquid microspheres with high exchange capacity for fast extraction of plasmid DNA

[Display omitted] •Polymeric ionic liquid (PIL) microspheres are adopted for DNA isolation.•Fast adsorption equilibrium of DNA on PIL is achieved within 1min.•The adsorption capacity of the PIL is much higher than that of the reported adsorbents. A novel polymeric ionic liquid (PIL) microsphere, poly(1-vinyl-3-(2-methoxy-2-oxyl ethyl)imidazolium) hexafluorophosphate, is prepared via W/O emulsion polymerization. Rapid ion-exchange between the anionic moieties of PIL and DNA fragments is demonstrated facilitating the exchange equilibrium to be reached within 1min. The PIL microspheres exhibit a high capacity of 190.7μgmg−1 for DNA adsorption. A fast DNA isolation protocol is thus developed with the PIL microspheres as solid phase adsorbent. It is feasible to facilitate DNA adsorption or stripping from the microspheres by simply regulating the concentration of salt. DNA adsorption is facilitated at low salt concentration, while higher concentration of salt entails DNA recovery from the microspheres. In practice, the retained DNA could be readily recovered with 1.0molL−1 NaCl as stripping reagent, giving rise to a recovery of ca. 80.7%. The PIL microspheres are used for the adsorption/isolation of plasmid DNA from E. coli cell culture, demonstrating a superior adsorption performance with respect to that achieved by a commercial Plasmid Miniprep Kit.