THIS GRANT IS A CONTINUATION OF N00014-14-1-0707 Self-Patterning DNA Materials
Abstract
The proposed research addresses the development of a molecular manufacturing technology that can program molecular self-organization across multiple length scales (nanometer to micron to centimeter). DNA self-assembly is a promising manufacturing technology that provides control at the nanometer and micron scales. This technology has been used to develop two- and three-dimensional DNA nanostructures, which have been used as scaffolds for metallic nanoparticles and enzymes leading to materials with novel optical and chemical properties. However, a method for programming molecular self-organization beyond the microscopic scale is missing. In this effort, engineered DNA species will be used to implement rationally designed reactionÐdiffusion systems to develop self-patterning materials with centimeter scale dimensions. Reaction-diffusion systems are mathematical models which explain how the spatial distribution of one or several substances change under the influence of (i) local chemical reactions, in which the substances are transformed into each other, and (ii) diffusion, which causes the substances to spread out in space. They have been suggested as the chemical basis for shape development in organisms and coat pattern formation in fish and mammals, and they have also been observed in non-biological chemical systems. In this effort, DNA molecules will be programmed to approximate the behavior of chemical reaction diffusion systems and yield self-organizing patterns with macroscopic dimensions. First, wave propagation will be investigated in a DNA-based autocatalytic reaction (A + B ? 2A, where a small amount of A effectively ÒconvertsÓ all of B to itself) with pre-patterned input. It will be determined what is required of the rate of an autocatalytic reaction to enable wave propagation over the distance of a centimeter or more. Aim 2 will demonstrate traveling wave behaviors using an engineered DNA-based reaction diffusion system. A predator prey reaction network will be implemented with DNA. A chemical predator prey model exhibits concentration oscillations for certain choices of the reaction rates in a well-mixed solution. If diffusion is added, the spatial propagation of traveling waves can be observed instead. Additionally, multiple waves can be expected rather than just a single wave front. For the DNA-based predator prey reaction network, exhibition of periodic oscillations in a well-mixed setting will be examined as will propagation of periodic traveling waves over centimeter distances. Aim 3 involves attempting to implement a DNA-based reaction-diffusion system that is capable of supporting stationary, self-organizing patterns (i.e. Turing patterns). The first model that will be attempted to be implemented with DNA to yield Turing patterns is the Brusselator model. The Brusselator model can be expressed as a set of chemical reactions: A ? X; 2X + Y ? 3X; B + X ? Y; and X ? ¯; where X is an activator and Y is an inhibitor. The activator facilitates the production of both itself and the inhibitor, through a non-linear autocatalytic feedback loop, while the inhibitor suppresses production of the activator. Furthermore, the inhibitor diffuses more rapidly than the activator. The Brusselator can exhibit periodic oscillations in a well-mixed reaction, but the oscillations approach a limit cycle independently of the initial concentrations of X and Y. It is envisioned that this technology for molecular self-organization at the macroscopic level can be combined with molecular self-assembly into a future manufacturing technology based entirely on programmed self-organization. Such a molecular manufacturing technology may yield adaptive materials with interesting optical, mechanical, or electronic properties.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jun 10, 2016
- Source ID
- N000141612139
Entities
People
- Georg Seelig
Organizations
- Office of Naval Research
- United States Navy
- University of Washington