title: Monitoring Protein Capsid Assembly with a Conjugated Polymer Strain Sensor.
abstract: Semiconducting polymers owe their optoelectronic properties to the delocalized electronic structure along their conjugated backbone. Their spectral features are therefore uniquely sensitive to the conformation of the polymer, where mechanical stretching of the chain leads to distinct vibronic shifts. Here we demonstrate how the optomechanical response of conjugated polyelectrolytes can be used to detect their encapsulation in a protein capsid. Coating of the sensor polymers by recombinant coat proteins induces their stretching due to steric hindrance between the proteins. The resulting mechanical planarizations lead to pronounced shifts in the vibronic spectra, from which the process of capsid formation can be directly quantified. These results show how the coupling between vibronic states and mechanical stresses inherent to conjugated polymers can be used to noninvasively measure strains at the nanoscale.
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Hande E
authors.initials: HE
authors.lastname: Cingil
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Ingeborg M
authors.initials: IM
authors.lastname: Storm
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Yelda
authors.initials: Y
authors.lastname: Yorulmaz
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Diane W
authors.initials: DW
authors.lastname: te Brake
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Renko
authors.initials: R
authors.lastname: de Vries
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Martien A
authors.initials: MA
authors.lastname: Cohen Stuart
authors.affiliation: Physical Chemistry and Soft Matter, Wageningen University, Dreijenplein 6, 6703 HB Wageningen, The Netherlands.
authors.forename: Joris
authors.initials: J
authors.lastname: Sprakel
mesh_terms: D036022:Capsid Proteins / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D011108:Polymers / Q000737:chemistry*; D012995:Solubility; D055672:Static Electricity; D013314:Stress, Mechanical; D014867:Water / Q000737:chemistry
chemical_list: D036022:Capsid Proteins; D011108:Polymers; D014867:Water