title: Cationic polymer brush-modified cellulose nanocrystals for high-affinity virus binding.
abstract: Surfaces capable of high-affinity binding of biomolecules are required in several biotechnological applications, such as purification, transfection, and sensing. Therein, the rod-shaped, colloidal cellulose nanocrystals (CNCs) are appealing due to their large surface area available for functionalization. In order to exploit electrostatic binding, their intrinsically anionic surfaces have to be cationized as biological supramolecules are predominantly anionic. Here we present a facile way to prepare cationic CNCs by surface-initiated atom-transfer radical polymerization of poly(N,N-dimethylaminoethyl methacrylate) and subsequent quaternization of the polymer pendant amino groups. The cationic polymer brush-modified CNCs maintained excellent dispersibility and colloidal stability in water and showed a ζ-potential of +38 mV. Dynamic light scattering and electron microscopy showed that the modified CNCs electrostatically bind cowpea chlorotic mottle virus and norovirus-like particles with high affinity. Addition of only a few weight percent of the modified CNCs in water dispersions sufficed to fully bind the virus capsids to form micrometer-sized assemblies. This enabled the concentration and extraction of the virus particles from solution by low-speed centrifugation. These results show the feasibility of the modified CNCs in virus binding and concentrating, and pave the way for their use as transduction enhancers for viral delivery applications.
authors.affiliation: Molecular Materials, Department of Applied Physics, Aalto University, P.O. Box 15100, FI-00076 Aalto, Espoo, Finland.
authors.forename: Henna
authors.initials: H
authors.lastname: Rosilo
authors.forename: Jason R
authors.initials: JR
authors.lastname: McKee
authors.forename: Eero
authors.initials: E
authors.lastname: Kontturi
authors.forename: Tiia
authors.initials: T
authors.lastname: Koho
authors.forename: Vesa P
authors.initials: VP
authors.lastname: Hytönen
authors.forename: Olli
authors.initials: O
authors.lastname: Ikkala
authors.forename: Mauri A
authors.initials: MA
authors.lastname: Kostiainen
mesh_terms: D000818:Animals; D000838:Anions; D001965:Bromides / Q000737:chemistry; D017795:Bromovirus; D002213:Capsid; D002412:Cations; D002460:Cell Line; D002482:Cellulose / Q000737:chemistry*; D003102:Colloids / Q000737:chemistry*; D006847:Hydrocarbons, Iodinated / Q000737:chemistry; D007313:Insecta; D008027:Light; D009682:Magnetic Resonance Spectroscopy; D008689:Methacrylates / Q000737:chemistry; D018625:Microscopy, Atomic Force; D046529:Microscopy, Electron, Transmission; D053758:Nanoparticles / Q000737:chemistry; D029322:Norovirus / Q000378:metabolism; D009757:Nylons / Q000737:chemistry; D011108:Polymers / Q000737:chemistry*; D011485:Protein Binding; D012542:Scattering, Radiation; D017550:Spectroscopy, Fourier Transform Infrared; D055672:Static Electricity; D013499:Surface Properties
chemical_list: D000838:Anions; D001965:Bromides; D002412:Cations; D003102:Colloids; D006847:Hydrocarbons, Iodinated; D008689:Methacrylates; D009757:Nylons; D011108:Polymers; C407037:poly(2-(dimethylamino)ethyl methacrylate); D002482:Cellulose; C014055:methyl iodide