Electric Field Directed Self-Assembly of Protein and DNA Derivatized Nanoparticles Into Higher-Order 3D Structures

A method is presented for the electric-field-directed self-assembly of higher-order structures composed of alternating layers of biotin nanoparticles and streptavidin-/avidin-conjugated enzymes carried out on a microelectrode array device. Enzymes included in the study were glucose oxidase (GOx), horseradish peroxidase (HRP), and alkaline phosphatase (AP); all of which could be used to form a light-emitting microscale glucose sensor. Directed assembly included fabricating multilayer structures with 200 nm or 40 nm GOx-avidin-biotin nanoparticles, with AP-streptavidin-biotin nanoparticles, and with HRP-streptavidin-biotin nanoparticles. Multilayered structures were also fabricated with alternate layering of HRP-streptavidin-biotin nanoparticles and GOx-avidin-biotin nanoparticles. Results showed that enzymatic activity was retained after the assembly process, indicating that substrates could still diffuse into the structures and that the electric-field-based fabrication process itself did not cause any significant loss of enzyme activity. These methods provide a solution to overcome the cumbersome passive layer-by-layer assembly methods to efficiently fabricate higher-order active biological and chemical hybrid structures that can be useful for creating novel biosensors and drug delivery nanostructures, as well as for diagnostic applications.

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Design of DNA Origami Machines and Mechanisms

Volume 9: Micro- and Nano-Systems Engineering and Packaging, Parts A and B ◽

10.1115/imece2012-87848 ◽

2012 ◽

Author(s):

Alex E. Marras ◽

Haijun J. Su ◽

Carlos E. Castro

Keyword(s):

Self Assembly ◽

Degrees Of Freedom ◽

Higher Order ◽

Dna Origami ◽

Motion Path ◽

3D Structures ◽

Detail Design ◽

Macro Scale ◽

Viable Approach ◽

Kinematic Mechanisms

This research introduces DNA origami as a viable approach to design and fabricate nanoscale mechanisms and machines. DNA origami is a recently developed nanotechnology that has enabled the construction of objects with unprecedented nanoscale geometric complexity via self-assembly. These objects are made up of thousands of DNA base-pairs packed into 3D structures with typical dimensions of 10–100nm. The majority of DNA origami research to date focuses on assembly of static 2D or 3D structures. In this work, we aim to extend the scope of DNA origami to include design of objects with kinematically constrained moving parts. Borrowing concepts from macro-scale kinematic mechanisms, we propose the concept of DNA Origami Mechanisms and Machines (DOMM) comprised of multiple links connected by joints. The links are designed by bundling double stranded DNA (dsDNA) helices to achieve the desired geometry and stiffness. The joints are designed by combining links with strategic placement flexible single stranded DNA (ssDNA) to enable motion in specific degrees of freedom. We detail design approaches for links and common joints including revolute, prismatic, and spherical, and discuss their integration into higher order mechanisms. As a proof of concept, we built a nanoscale hinge (revolute joint) and integrated four of these hinges into a prototype DOMM, namely a Bennett 4-bar linkage, which can be completely folded into a closed bundle geometry and unfolded into an open square geometry with a specified kinematic motion path. A kinematic analysis shows that the DNA Bennett linkage closely follows the 3D motion path of the rigid body counterpart. Our results demonstrate that DNA origami has high potential for the design and assembly of nanoscale machines. The ultimate goal of this work is to develop a library of nanoscale DNA-based links and joints that can be widely used in the design and assembly of higher order mechanisms and machines. We anticipate that, in the future, these components can be used to build nanorobots for useful applications including drug delivery, nanomanufacturing, and biosensing.

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An In-Situ Reaction Route to Molecular Level Dispersed Bisimide and ZnO Nanorod Hybrids with Efficient Photo-Induced Charge Transfer

Nanoscale Research Letters ◽

10.1186/s11671-021-03504-3 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Chunzheng Lv ◽

Lirong He ◽

Jiahong Tang ◽

Feng Yang ◽

Chuhong Zhang

Keyword(s):

Charge Transfer ◽

Electric Field ◽

Self Assembly ◽

Molecular Level ◽

Surface Photovoltage ◽

Zno Nanorod ◽

In Situ Reaction ◽

Perylene Bisimide ◽

Induced Charge

AbstractAs an important photoconductive hybrid material, perylene/ZnO has attracted tremendous attention for photovoltaic-related applications, but generally faces a great challenge to design molecular level dispersed perylenes/ZnO nanohybrids due to easy phase separation between perylenes and ZnO nanocrystals. In this work, we reported an in-situ reaction method to prepare molecular level dispersed H-aggregates of perylene bisimide/ZnO nanorod hybrids. Surface photovoltage and electric field-induced surface photovoltage spectrum show that the photovoltage intensities of nanorod hybrids increased dramatically for 100 times compared with that of pristine perylene bisimide. The enhancement of photovoltage intensities resulting from two aspects: (1) the photo-generated electrons transfer from perylene bisimide to ZnO nanorod due to the electric field formed on the interface of perylene bisimide/ZnO; (2) the H-aggregates of perylene bisimide in ZnO nanorod composites, which is beneficial for photo-generated charge separation and transportation. The introduction of ordered self-assembly thiol-functionalized perylene-3,4,9,10-tetracarboxylic diimide (T-PTCDI)/ ZnO nanorod composites induces a significant improvement in incident photo-to-electron conversion efficiency. This work provides a novel mentality to boost photo-induced charge transfer efficiency, which brings new inspiration for the preparation of the highly efficient solar cell.

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Self-Assembly of Monolayers of Submicron Sized Particles on Thin Liquid Films

Volume 7A: Fluids Engineering Systems and Technologies ◽

10.1115/imece2013-65324 ◽

2013 ◽

Author(s):

Shriram Pillapakkam ◽

N. A. Musunuri ◽

P. Singh

Keyword(s):

Electric Field ◽

Self Assembly ◽

Uv Light ◽

Capillary Forces ◽

Liquid Films ◽

Thin Liquid Films ◽

Liquid Interfaces ◽

Uv Curable ◽

Particle Monolayer ◽

Uv Curable Resin

In this paper, we present a technique for freezing monolayers of micron and sub-micron sized particles onto the surface of a flexible thin film after the self-assembly of a particle monolayer on fluid-liquid interfaces has been improved by the process we have developed where an electric field is applied in the direction normal to the interface. Particles smaller than about 10 microns do not self-assemble under the action of lateral capillary forces alone since capillary forces amongst them are small compared to Brownian forces. We have overcome this problem by applying an electric field in the direction normal to the interface which gives rise to dipoledipole and capillary forces which cause the particles to arrange in a triangular pattern. The technique involves assembling the monolayer on the interface between a UV-curable resin and another liquid by applying an electric field, and then curing the resin by applying UV light. The monolayer becomes embedded on the surface of the solidified resin film.

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Numerical Simulations of Electric Field Driven Self-Assembly of Monolayers of Mixtures of Nanoparticles

Volume 1B, Symposia: Fluid Measurement and Instrumentation; Fluid Dynamics of Wind Energy; Renewable and Sustainable Energy Conversion; Energy and Process Engineering; Microfluidics and Nanofluidics; Development and Applications in Computational Fluid Dynamics; DNS/LES and Hybrid RANS/LES Methods ◽

10.1115/fedsm2017-69380 ◽

2017 ◽

Author(s):

E. Amah ◽

N. Musunuri ◽

Ian S. Fischer ◽

Pushpendra Singh

Keyword(s):

Electric Field ◽

Physical Properties ◽

Numerical Simulations ◽

Self Assembly ◽

Composite Particle ◽

Critical Value ◽

Direct Numerical Simulations ◽

Composite Particles ◽

Liquid Interfaces ◽

Induced Dipole

We numerically study the process of self-assembly of particle mixtures on fluid-liquid interfaces when an electric field is applied in the direction normal to the interface. The force law for the dependence of the electric field induced dipole-dipole and capillary forces on the distance between the particles and their physical properties obtained in an earlier study by performing direct numerical simulations is used for conducting simulations. The inter-particle forces cause mixtures of nanoparticles to self-assemble into molecular-like hierarchical arrangements consisting of composite particles which are organized in a pattern. However, there is a critical electric intensity value below which particles move under the influence of Brownian forces and do not self-assemble. Above the critical value, when the particles sizes differed by a factor of two or more, the composite particle has a larger particle at its core and several smaller particles forming a ring around it. Approximately same sized particles, when their concentrations are approximately equal, form binary particles or chains (analogous to polymeric molecules) in which positively and negatively polarized particles alternate, but when their concentrations differ the particles whose concentration is larger form rings around the particles with smaller concentration.

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