Abstract
A poly(oligo(ethylene glycol) monomethyl ether methacrylate)-block-poly(N-isopropyl methacrylamide) (POEGMA-b-PNIPMAM) block copolymer with a biotin end group on the PNIPMAM block as a biotarget was synthesized as a model system for temperature-controlled polymer immobilization. The synthesis was based on RAFT polymerization followed by postpolymerization modification of an activated ester precursor block and an exchange of the dithioester end group within one step. NMR, differential scanning calorimetry (DSC), dynamic light scattering (DLS), and turbidimetry measurements were performed to investigate the stimulus-responsive properties. The double thermoresponsive POEGMA-b-PNIPMAM with biotin end group showed a temperature-dependent multistage assembly behavior as it was completely soluble in water at temperatures below the LCST of both blocks, formed micellar structures above the LCST of PNIPMAM but below the LCST of POEGMA, or precipitated from solution above the LCST of both blocks. At room temperature, the polymer could be immobilized onto a streptavidin surface via its biotin end group, as shown in surface plasmon resonance (SPR) experiments. At 50 °C, at which the block copolymer formed micelles trapping the biotin target within the PNIPMAM core, no immobilization was observed, showing that the biological binding ability of the model could be controlled via external stimuli.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.