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- Bunk, Richard, et al.
(författare)
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Actomyosin motility on nanostructured surfaces
- 2003
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Ingår i: Biochemical and Biophysical Research Communications. - 1090-2104. ; 301:3, s. 783-788
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Tidskriftsartikel (refereegranskat)abstract
- We have here, for the first time, used nanofabrication techniques to reproduce aspects of the ordered actomyosin arrangement in a muscle cell. The adsorption of functional heavy meromyosin (HMM) to five different resist polymers was first assessed. One group of resists (MRL-6000.1XP and ZEP-520) consistently exhibited high quality motility of actin filaments after incubation with HMM. A second group (PMMA-200, PMMA-950, and MRI-9030) generally gave low quality of motility with only few smoothly moving filaments. Based on these findings electron beam lithography was applied to a bi-layer resist system with PMMA-950 on top of MRL-6000.1XP. Grooves (100-200 nm wide) in the PMMA layer were created to expose the MRL-6000.1XP surface for adsorption of HMM and guidance of actin filament motility. This guidance was quite efficient allowing no U-turns of the filaments and approximately 20 times higher density of moving filaments in the grooves than on the surrounding PMMA.
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- Bunk, Richard, et al.
(författare)
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Guiding molecular motors with nano-imprinted structures
- 2005
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Ingår i: Japanese Journal of Applied Physics. - 0021-4922. ; 44:5A, s. 3337-3340
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Tidskriftsartikel (refereegranskat)abstract
- This work, for the first time, demonstrates that nano-imprinted samples, with 100 nm wide polymer lines, can act as guides for molecular motors consisting of motor proteins actin and myosin. The motor protein function was characterized using fluorescence microscopy and compared to actomyosin motility on non-structured nitrocellulose surfaces. Our results open for further use of the nano-imprint technique in the production of disposable chips for bio-nanotechnological applications and miniaturized biological test systems. We discuss how the nano-imprinted motor protein assay system may be optimized and also how it compares to previously tested assay systems involving low-resolution UV-lithography and low throughput but high-resolution electron beam lithography.
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- Bunk, Richard, et al.
(författare)
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Guiding motor-propelled molecules with nanoscale precision through silanized bi-channel structures
- 2005
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Ingår i: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 16:6, s. 710-717
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Tidskriftsartikel (refereegranskat)abstract
- We report on the design and fabrication of a channel structure for high precision guidance and achieving excellent confinement properties for motor-propelled molecular shuttles. The techniques used to manufacture the channel structure are mainly e-beam lithography and selective monolayer functionalization. The structure consists of two lateral layers of concentric channels on a SiO2 surface made biocompatible with the molecular motors. The quality and advantages of the design are demonstrated by experiments using the motor proteins actin and myosin. The special channel geometry leads to stable biochemical conditions with full motor protein functionality. ATP is sufficiently supplied to all parts of the structure by dedicated service channels, as is the venting of ADP and P-i (inorganic phosphorus). Channels of different widths (100-700 nm) and shapes are fabricated and measurements made on them.
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- Bunk, Richard, et al.
(författare)
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Towards a 'nano-traffic' system powered by molecular motors
- 2003
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Ingår i: Microelectronic Engineering. - 1873-5568. ; 67-8, s. 899-904
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Tidskriftsartikel (refereegranskat)abstract
- In this work, we reconstructed in vitro the behavior of two motor proteins-myosin and actin-responsible for the mechanical action of muscle cells. By transferring this in vivo system to an artificial environment, we were able to study the interaction between the proteins in more detail, as well as investigating the central mechanism of force production. Nm-patterning by e-beam lithography (EBL) could restore parts of the in vivo protein order, essential for potential nanotechnological applications. Much work was put into establishing the necessary compatibility between the biological and nano-lithographical processes. A range of EBL-resists were tested for protein compatibility. One particular kind (MRL-6000.1XP) supported good actin filament motility, while another (PMMA-950) behaved in the opposite way. Taking advantage of these findings, nm-sized lines were created in a double-layer structure of the two resists. The lines were found to act as binding sites for myosin, and as rectifying guides for the linearized motion of actin filaments. Velocities around 5 mum/s were measured. (C) 2003 Elsevier Science B.V. All rights reserved.
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- Mansson, A, et al.
(författare)
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Actin-based molecular motors for cargo transportation in nanotechnology - Potentials and challenges
- 2005
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Ingår i: IEEE Transactions on Advanced Packaging. - 1521-3323. ; 28:4, s. 547-555
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Tidskriftsartikel (refereegranskat)abstract
- Here, we review the use of actin-based motors, (myosins; e.g., the molecular motor of muscle) in. nanotechnology. The review starts from the viewpoints of the molecular motors as being important devices responsible of cargo transportation in the cell and end in discussions about their employment in nanotechnological applications. First, we describe basic biophysics of the myosin motors with focus on their involvement in cargo transportation in the living cell, leading us over into a discussion about in vitro motility assays. These are biological test systems where the myosin-induced translocation of actin filaments is studied on an artificial surface outside the cell. Then follows a review about modified motility assays for production of ordered motion. Here, we discuss ours and others' work with regards to making micro- and nanostructured surfaces and channels where the position and direction of movement produced by molecular motors is controlled. In this section, we consider the role of the channel size in promoting unidirectional myosin-induced motion of actin filaments. Furthermore, we consider the usefulness of surface modifications, e.g., various silanization procedures in order to promote and hinder molecular motility, respectively. Particularly, we describe our latest test system being both morphologically and chemically nanostructured giving us unsurpassed possibilities to perform functional studies as well as extremely good spatio-temporal control. Then follows a section about nanotechnological cargo transportation systems based on the actomyosin motor system. For instance, we present results of attaching fluorescent quantum dots as cargoes to the actin filaments. In this section, we also discuss the possibilities of having cargo attachment and detachment being performed on demand. Finally, we consider the usefulness of molecular motors for lab-on-a-chip applications and the requirements for incorporating these motors in commercially viable devices. In this context, the significant potential of the actomyosin motor system to overcome traditional limitations of micro- and nanofluidics is stressed.
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