Hybrid hydrogel microspheres loading single-hole hollow imprinted particles for fast and selective uptake of 2′-deoxyadenosine

Hydrogel microspheres encapsulating molecularly imprinted polymers (MIPs) are promising hybrid sorbents, due to several advantages of high selectivity, fast mass transfer efficiency, and simple collection. Thus, Janus single-hole hollow nanoparticles (J-HNPs) with the size of 550 ± 70 nm were firstly designed by anisotropic emulsion template, and then MIPs were grafted onto their inner surface through electron transfer atom transfer radical polymerization (ARGET ATRP). Then as-prepared J-HNPs-MIPs were loaded into hydrogel microspheres via polymerizable water-in-oil (W/O) emulsion droplets combining gelatin methacryloyl (GMA) as monomers, and then obtained J-HNPs-MIPs@Gel with the mean diameter of 2.0 µm was applied for effective and selective separation of 2′-deoxyadenosine (dA). Fast adsorption equilibrium of J-HNPs-MIPs@Gel for dA can be achieved within 40 min, thanks to the hydrogel matrix and single-hole hollow structure for enhancing diffusion. The maximum multi-layer adsorption capacity calculated according to the Freundlich model was 10.31 μmol g −1 at 298 K. The specific memory to the size, shape and functional groups of dA endowed excellent recognition ability, and 88% of the initial capacity after four consecutive adsorption-desorption cycles was maintained. In addition, J-HNPs-MIPs@Gel was expected to show great potential for the selective enrichment and analysis of target dA molecule in complex biological samples.