title: Transient viscoelasticity study of tobacco mosaic virus/Ba(2+) superlattice.
abstract: Recently, we reported a new method to synthesize the rod-like tobacco mosaic virus (TMV) superlattice. To explore its potentials in nanolattice templating and tissue scaffolding, this work focused the viscoelasticity of the superlattice with a novel transient method via atomic force microscopy (AFM). For measuring viscoelasticity, in contrast to previous methods that assessed the oscillating response, the method proposed in this work enabled us to determine the transient response (creep or relaxation) of micro/nanobiomaterials. The mathematical model and numerical process were elaborated to extract the viscoelastic properties from the indentation data. The adhesion between the AFM tip and the sample was included in the indentation model. Through the functional equation method, the elastic solution for the indentation model was extended to the viscoelastic solution so that the time dependent force vs. displacement relation could be attained. To simplify the solving of the differential equation, a standard solid model was modified to obtain the elastic and viscoelastic components of the sample. The viscoelastic responses with different mechanical stimuli and the dynamic properties were also investigated.
authors.affiliation: Department of Mechanical Engineering, North Dakota State University, Fargo ND 58108, USA.
authors.forename: Haoran
authors.initials: H
authors.lastname: Wang
authors.affiliation: Department of Mechanical Engineering, North Dakota State University, Fargo ND 58108, USA.
authors.forename: Xinnan
authors.initials: X
authors.lastname: Wang
authors.affiliation: X-ray Science Division, Advanced Photon Source of Argonne National Laboratory, 9700 S. Cass Avenue, Argonne IL 60439, USA.
authors.forename: Tao
authors.initials: T
authors.lastname: Li
authors.affiliation: X-ray Science Division, Advanced Photon Source of Argonne National Laboratory, 9700 S. Cass Avenue, Argonne IL 60439, USA.
authors.forename: Byeongdu
authors.initials: B
authors.lastname: Lee
keywords: Atomic force microscopy; Nanoindentation; Tobacco mosaic virus; Viscoelasticity