PNIPAm hydrogel composite membrane for high-throughput adsorption of biological macromolecules

•PNIPAm based hydrogel composite membranes (HCM) were developed for protein absorption.•CS-PNIPAm HCM achieved high adsorption capacity under wide temperature range.•PEGDA-PNIPAm HCM significantly improved the adsorption capacity at 32℃. High-throughput enrichment of biomacromolecules is important in biomedicine, drug release and immobilized enzymes, etc. Herein, two poly-N-isopropylacrylamide (PNIPAm)-based hydrogel composite membrane (HCM), which remarked as PEGDA-PNIPAm and CS-PNIPAm, were fabricated for the adsorption of bovine serum albumin (BSA) under different conditions by introducing using polyethylene glycol diacrylate (PEGDA) and chitosan (CS) as monomers. Fabricated PNIPAm-based HCM exhibits excellent structural stability, thermal stability, and good pH sensitivity. The presence of CS in CS-PNIPAm hindered the temperature response of PNIPAm and possessed stable adsorption capacities over a wide temperature range (average 296.4 ± 50 mg g−1 from 10℃ to 37℃). PEGDA-PNIPAm HCM achieves the highest adsorption capacity (457.0 mg g−1) around the transition temperature of 32 °C (457.0 mg g−1). The results indicated that the developed HCM materials have potential applications for high-throughput protein adsorption.