Selective attachment of F-actin with controlled length for developing an intelligent nanodevice.
Development of the nanodevice that myosin-coated beads "walk" on actin filaments (F-actin) tracks for in vitro nanotransportation was hindered due to the difficulty of assembling large-area well-orientated F-actin tracks on the surface. In this work, we present a selective attachment of F-actin with controlled length on a patterned surface by employing biotinylated capped protein gelsolin as intermediate anchoring bridge. A patterned streptavidin layer was formed via coupling with a biotin layer that photo-actively attached to an amine-functionalized glass surface. The patterned film was found stable and homogenous compared to that obtained by microcontact printing method, according to the profiling with fluorescence microscopy. By a secondary blocking process, non-specific binding of F-actin to the patterned surface through electrostatic adsorption can be resisted. The length variation of F-actin as a function of gelsolin concentration was also investigated, implying that F-actin is appropriately of 2.5 μm in average length once F-actin/gelsolin molar ratio is 4:1. Finally, the selective attachment of F-actin was well characterized with quantifying the number of attached F-actin per unit area in the patterned areas over that in blocked areas. The density of F-actin was estimated at c.a. 2 μm(2) per actin filament molecule so that the distance between one another actin filament is estimated as c.a. 1.41-1.97 μm. The unique properties of F-actin, e.g. well flexibility or electrical conductivity, make it feasible to lay them down and form unidirectional aligned tracks by fluidic flow or electrical field. This may open a possibility for the long-distant movement of myosin-coated beads, offering a novel discipline for the development of micro-biochip in vitro.
Lane Department of Computer Science and Electrical Engineering, West Virginia University, Morgantown, WV 26506, USA. ming-yuan.wei@mail.wvu.edu
Ming-Yuan
MY
Wei
Lenin J
LJ
Leon
Yongkuk
Y
Lee
Denzel
D
Parks
Lloyd
L
Carroll
Parviz
P
Famouri
D008841:Actin Cytoskeleton / Q000737:chemistry / Q000378:metabolism*; D000199:Actins / Q000737:chemistry / Q000378:metabolism*; D001665:Binding Sites; D001710:Biotin / Q000737:chemistry / Q000378:metabolism; D019921:Biotinylation; D018260:Gelsolin / Q000378:metabolism; D005898:Glass / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D008856:Microscopy, Fluorescence; D009068:Movement; D009218:Myosins / Q000737:chemistry / Q000378:metabolism*; D036103:Nanotechnology / Q000379:methods; D011485:Protein Binding; D019809:Streptavidin / Q000737:chemistry / Q000378:metabolism; D013499:Surface Properties
D000199:Actins; D018260:Gelsolin; D001710:Biotin; D019809:Streptavidin; D009218:Myosins