Temperature‐Switchable Assembly of Supramolecular Virus–Polymer Complexes

Abstract

Here a method is presented for the temperature‐switchable assembly of viral particles into large hierarchical complexes. Dual‐functional diblock copolymers consisting of poly(diethyleneglycol methyl ether methacry­late) (poly(DEGMA)) and poly((2‐dimethylamino)ethyl methacrylate) (poly(DMAEMA)) blocks self‐assemble electrostatically with cowpea chlorotic mottle virus (CCMV) particles into micrometer‐sized objects as a function of temperature. The poly(DMAEMA) block carries a positive charge, which can interact electrostatically with the negatively charged outer surface of the CCMV capsid. When the solution temperature is increased above 40 °C, to cross the cloud point temperature (Tcp) of the DEGMA block, the polymer chains collapse on the surface of the virus particle, which makes them partially hydrophobic, and consequently causes the formation of large hierarchical assemblies. Disassembly of the virus–polymer complexes can be induced by reducing the solution temperature below the Tcp, which allows the poly(DEGMA) blocks to rehydrate and free virus particles to be released. The assembly process is fully reversible and can sustain several heating–cooling cycles. Importantly, this method relies on reversible supramolecular interactions and therefore avoids the irreversible covalent modification of the particle surface. This study illustrates the potential of temperature‐responsive polymers for controlled binding and releasing of virus particles.

Modeling Viral Capsid Assembly

“…Namely, experiments have been performed in which capsid proteins assemble into icosahedral capsids around various cargoes including genomic or non-genomic RNA (e.g. [18–20, 43, 114, 115, 121, 142, 149, 264]), synthetic polyelectrolytes [20, 37, 38, 60, 114, 117, 147, 171, 232], charge-functionalized nanoparticles [68, 97, 122, 163, 164, 241, 251], DNA micelles [151] and nano-emulsions [49]. However, as discussed further below features specific to biological RNA molecules such as their tertiary structure and sequence-specific interactions likely promote selective assembly around the viral genome or help direct assembly toward particular morphologies.…”

Quantum-Dot-Induced Self-Assembly of Cricoid Protein for Light Harvesting

“…The screening is characterized by the Debye length, κ À1 , which can be defined as the distance over which the Coulombic interactions are canceled by the screening effect of the counterions. 24 At 250 mM NaCl concentration, the κ À1 is ≈2 nm, which is not small enough to disperse all the assembly. In contrast, the κ À1 is ≈11 nm at 10 mM NaCl, which will not affect the electrostatic self-assembly at all.…”

RAFT polymerization of temperature- and salt-responsive block copolymers as reversible hydrogels

“…Random copolymers containing hydrophilic monomers such as OEG [22], 2-dimethylaminoethyl methacrylate (DMA) [23], or methacrylic acid [23] enabled the tuning of the LCST. Multiple researchers examined poly(DEG- b -DMA) diblock copolymers for their temperature- and pH-responsive micellization behavior [24,25]. Müller et al [26] synthesized DEG and DMA star block copolymers with a DMA core and DEG shell.…”