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Fail-safes in nanotechnology are devices or features integrated with nanotechnology which, in the event of failure, respond in a way that will cause no harm, or at least a minimum of harm, to other devices or personnel. Fail-safe principles are governed by national standards and engineering practices, and are widely used in conventional engineering design. It is possible to scale down macro-scale fail-safe principles and devices for similar applications at the nano-scale. [1] The use of fail-safes in nanotechnology applications supports social acceptance of those applications by reducing the risks to users; as of 2009 [update] , there are both theoretical and practical ways to implement fail-safe designs in nanotechnology.[ citation needed ]
A predominant challenge to the social acceptance of nanotechnology is concerned with the medical use of nanostructures in the human body. While any structure for medical use would be developed to be bio-compatible and harmless, sound engineering design must take into account all possibilities of failure. Thus, the design would include ways to manipulate the structures in the body in the event of failure.
Many researchers are looking into creating nano-scale robots (“nanobots”), for the purpose of undertaking tasks where only robots on the nano scale can be used, such as inside the human body. These robots would have the ability to construct other nanostructures or perform medical procedures, and will be introduced into the body via an injection. [2] The robots’ shells and circuits would be made of ferrous nanoparticles so that a magnetic field could be used to prevent or manipulate their movement. In case of failure or malfunction, a small EMP or an MRI could be used to deactivate the nanobots. Both techniques induce an electromagnetic field, corrupting the memory and shorting out the circuitry of any electronic device within range.
Researchers are pursuing the building of nanostructures using amino acids. Nanostructures that are created using amino acids are constructed using only synthetic types of amino acids, which tags these structures with unique molecules. These engineered amino acids essentially form synthetic proteins that differ from the naturally occurring proteins in the human body. This difference in the engineered amino acids makes these proteins easy to isolate and target. [3] In case of failure or malfunction, it is possible to identify these proteins using the specifically targeted molecules, which act as a flag to indicate the location of the target. Then, another mechanism would be used to isolate them and deactivate them.
DNA within our bodies naturally breaks down, replicates itself, and replenishes itself every time a cell divides. These processes are all controlled and completed by various enzymes. DNA molecules are composed of corresponding base pair nucleotides in a double-helix formation, which makes these processes very efficient, accurate, and predictable. Due to the ease with which DNA molecules can be fashioned, many publications in the academic society are geared towards creating nanostructures using DNA. [4] With a DNA-based nano-device, synthetic proteins could be created, designed to deactivate a nano-device. These synthetic proteins would be injected into the body to break down the DNA and render a nano-device harmless in the event of a malfunction.
Biological proteins within the human body serve three main functions: they are structural building blocks, enzymes, and facilitate cellular signaling. Synthetic proteins could be developed as a form of indicator and attached to a DNA-based nano-device. [5] This indicator would then be used for the purpose of monitoring nano-devices in the human body. If all DNA-based nano-devices were closely monitored in the human body, they could be controlled quickly in the event of a malfunction.
In nanotechnology, particularly in nanobots, the need for a sound programming architecture is important due to a potentially higher risk of damage in the event of a malfunction. A two-layer approach can be used to control nano-devices: (1) by providing a preprogrammed fail-safe functionality in case of anticipated failures; and (2) a remote-controlled override for use in unforeseen situations. [6] The “remote”-controlled nano-device would require a specialist in the room, to guide the nanobot throughout the procedure.
Many researchers are developing methods that use bacteria to deliver drugs. [7] These bacteria can be “programmed” to perform a specific task, and can be directed to go to targeted locations in the body. [8] However, the bacteria may damage healthy organs or fail to deliver the medicine to the sick organ in the case of a malfunction. In such cases, a fail-safe mechanism is required to neutralize the bacteria and prevent damage. An antibiotic is generally suitable as the fail-safe agent.
Nanotechnology was defined by the National Nanotechnology Initiative as the manipulation of matter with at least one dimension sized from 1 to 100 nanometers (nm). At this scale, commonly known as the nanoscale, surface area and quantum mechanical effects become important in describing properties of matter. The definition of nanotechnology is inclusive of all types of research and technologies that deal with these special properties. It is therefore common to see the plural form "nanotechnologies" as well as "nanoscale technologies" to refer to the broad range of research and applications whose common trait is size. An earlier description of nanotechnology referred to the particular technological goal of precisely manipulating atoms and molecules for fabrication of macroscale products, also now referred to as molecular nanotechnology.
A macromolecule is a very large molecule important to biological processes, such as a protein or nucleic acid. It is composed of thousands of covalently bonded atoms. Many macromolecules are polymers of smaller molecules called monomers. The most common macromolecules in biochemistry are biopolymers and large non-polymeric molecules such as lipids, nanogels and macrocycles. Synthetic fibers and experimental materials such as carbon nanotubes are also examples of macromolecules.
A molecular assembler, as defined by K. Eric Drexler, is a "proposed device able to guide chemical reactions by positioning reactive molecules with atomic precision". A molecular assembler is a kind of molecular machine. Some biological molecules such as ribosomes fit this definition. This is because they receive instructions from messenger RNA and then assemble specific sequences of amino acids to construct protein molecules. However, the term "molecular assembler" usually refers to theoretical human-made devices.
Nanosensors are nanoscale devices that measure physical quantities and convert these to signals that can be detected and analyzed. There are several ways proposed today to make nanosensors; these include top-down lithography, bottom-up assembly, and molecular self-assembly. There are different types of nanosensors in the market and in development for various applications, most notably in defense, environmental, and healthcare industries. These sensors share the same basic workflow: a selective binding of an analyte, signal generation from the interaction of the nanosensor with the bio-element, and processing of the signal into useful metrics.
A nanopore is a pore of nanometer size. It may, for example, be created by a pore-forming protein or as a hole in synthetic materials such as silicon or graphene.
Nanoid robotics, or for short, nanorobotics or nanobotics, is an emerging technology field creating machines or robots whose components are at or near the scale of a nanometer. More specifically, nanorobotics refers to the nanotechnology engineering discipline of designing and building nanorobots with devices ranging in size from 0.1 to 10 micrometres and constructed of nanoscale or molecular components. The terms nanobot, nanoid, nanite, nanomachine and nanomite have also been used to describe such devices currently under research and development.
Xenobiology (XB) is a subfield of synthetic biology, the study of synthesizing and manipulating biological devices and systems. The name "xenobiology" derives from the Greek word xenos, which means "stranger, alien". Xenobiology is a form of biology that is not (yet) familiar to science and is not found in nature. In practice, it describes novel biological systems and biochemistries that differ from the canonical DNA–RNA-20 amino acid system. For example, instead of DNA or RNA, XB explores nucleic acid analogues, termed xeno nucleic acid (XNA) as information carriers. It also focuses on an expanded genetic code and the incorporation of non-proteinogenic amino acids into proteins.
Nanobiotechnology, bionanotechnology, and nanobiology are terms that refer to the intersection of nanotechnology and biology. Given that the subject is one that has only emerged very recently, bionanotechnology and nanobiotechnology serve as blanket terms for various related technologies.
The use of nanotechnology in fiction has attracted scholarly attention. The first use of the distinguishing concepts of nanotechnology was "There's Plenty of Room at the Bottom", a talk given by physicist Richard Feynman in 1959. K. Eric Drexler's 1986 book Engines of Creation introduced the general public to the concept of nanotechnology. Since then, nanotechnology has been used frequently in a diverse range of fiction, often as a justification for unusual or far-fetched occurrences featured in speculative fiction.
DNA origami is the nanoscale folding of DNA to create arbitrary two- and three-dimensional shapes at the nanoscale. The specificity of the interactions between complementary base pairs make DNA a useful construction material, through design of its base sequences. DNA is a well-understood material that is suitable for creating scaffolds that hold other molecules in place or to create structures all on its own.
Nanotechnology is impacting the field of consumer goods, several products that incorporate nanomaterials are already in a variety of items; many of which people do not even realize contain nanoparticles, products with novel functions ranging from easy-to-clean to scratch-resistant. Examples of that car bumpers are made lighter, clothing is more stain repellant, sunscreen is more radiation resistant, synthetic bones are stronger, cell phone screens are lighter weight, glass packaging for drinks leads to a longer shelf-life, and balls for various sports are made more durable. Using nanotech, in the mid-term modern textiles will become "smart", through embedded "wearable electronics", such novel products have also a promising potential especially in the field of cosmetics, and has numerous potential applications in heavy industry. Nanotechnology is predicted to be a main driver of technology and business in this century and holds the promise of higher performance materials, intelligent systems and new production methods with significant impact for all aspects of society.
Biological computers use biologically derived molecules — such as DNA and/or proteins — to perform digital or real computations.
Biomolecular engineering is the application of engineering principles and practices to the purposeful manipulation of molecules of biological origin. Biomolecular engineers integrate knowledge of biological processes with the core knowledge of chemical engineering in order to focus on molecular level solutions to issues and problems in the life sciences related to the environment, agriculture, energy, industry, food production, biotechnology and medicine.
The following outline is provided as an overview of and topical guide to nanotechnology:
The Technology Roadmap for Productive Nanosystems defines "productive nanosystems" as functional nanoscale systems that make atomically-specified structures and devices under programmatic control, i.e., they perform atomically precise manufacturing. Such devices are currently only hypothetical, and productive nanosystems represents a more advanced approach among several to perform Atomically Precise Manufacturing. A workshop on Integrated Nanosystems for Atomically Precise Manufacturing was held by the Dept. of Energy in 2015.
Self-assembling peptides are a category of peptides which undergo spontaneous assembling into ordered nanostructures. Originally described in 1993, these designer peptides have attracted interest in the field of nanotechnology for their potential for application in areas such as biomedical nanotechnology, tissue cell culturing, molecular electronics, and more.
DNA nanotechnology is the design and manufacture of artificial nucleic acid structures for technological uses. In this field, nucleic acids are used as non-biological engineering materials for nanotechnology rather than as the carriers of genetic information in living cells. Researchers in the field have created static structures such as two- and three-dimensional crystal lattices, nanotubes, polyhedra, and arbitrary shapes, and functional devices such as molecular machines and DNA computers. The field is beginning to be used as a tool to solve basic science problems in structural biology and biophysics, including applications in X-ray crystallography and nuclear magnetic resonance spectroscopy of proteins to determine structures. Potential applications in molecular scale electronics and nanomedicine are also being investigated.
Wet nanotechnology involves working up to large masses from small ones.
RNA origami is the nanoscale folding of RNA, enabling the RNA to create particular shapes to organize these molecules. It is a new method that was developed by researchers from Aarhus University and California Institute of Technology. RNA origami is synthesized by enzymes that fold RNA into particular shapes. The folding of the RNA occurs in living cells under natural conditions. RNA origami is represented as a DNA gene, which within cells can be transcribed into RNA by RNA polymerase. Many computer algorithms are present to help with RNA folding, but none can fully predict the folding of RNA of a singular sequence.
This glossary of nanotechnology is a list of definitions of terms and concepts relevant to nanotechnology, its sub-disciplines, and related fields.