title: Polymer nanoparticle hydrogels with autonomous affinity switching for the protection of proteins from thermal stress.
abstract: We report a new material design concept for synthetic, thermally responsive poly(N-isopropylacrylamide)-based copolymer nanoparticle (NP) hydrogels, which protect proteins from thermal stress. The NP hydrogels bind and protect a target enzyme from irreversible activity loss upon exposure to heat but "autonomously" release the enzyme upon subsequent cooling of the solution. Incorporation of the optimized amount of negatively charged and hydrophobic comonomers to the NP hydrogels was key to achieve these desired functions. As the NP hydrogels do not show a strong affinity for the enzyme at room temperature, they can remain in solution without adversely affecting enzymatic activity or they can be removed by filtration to leave the enzyme in solution. The results demonstrate the promise of this approach for improving the thermal tolerance of proteins.
authors.affiliation: Department of Chemistry, University of California, Irvine, Irvine, CA 92697 (USA).
authors.forename: John M
authors.initials: JM
authors.lastname: Beierle
authors.forename: Keiichi
authors.initials: K
authors.lastname: Yoshimatsu
authors.forename: Beverly
authors.initials: B
authors.lastname: Chou
authors.forename: Michael A A
authors.initials: MA
authors.lastname: Mathews
authors.forename: Benjamin K
authors.initials: BK
authors.lastname: Lesel
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Shea
mesh_terms: D020100:Hydrogels / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D053758:Nanoparticles / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry*; D013696:Temperature
chemical_list: D020100:Hydrogels; D011108:Polymers; D011506:Proteins
keywords: nanoparticles; noncovalent interactions; phase transitions; polymers; proteins