Fail-safe In engineering, a fail-safe is a design feature or practice that in the event of a specific type of failure, inherently responds in a way that will cause minimal or no harm to other equipment, to the environment or to people. Unlike inherent safe ...

s 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. The use of fail-safes in nanotechnology applications supports social acceptance of those applications by reducing the risks to users; , there are both theoretical and practical ways to implement

fail-safe In engineering, a fail-safe is a design feature or practice that in the event of a specific type of failure, inherently responds in a way that will cause minimal or no harm to other equipment, to the environment or to people. Unlike inherent safe ...

designs in nanotechnology. 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.

Ferrous nanoparticles

Many researchers are looking into creating nano-scale robots (“

nanobots 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 (10−9 meters). More specifically, nanorobotics (as opposed to mi ...

”), 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. The robots’ shells and circuits would be made of

ferrous In chemistry, the adjective Ferrous indicates a compound that contains iron(II), meaning iron in its +2 oxidation state, possibly as the divalent cation Fe2+. It is opposed to " ferric" or iron(III), meaning iron in its +3 oxidation state, suc ...

nanoparticle A nanoparticle or ultrafine particle is usually defined as a particle of matter that is between 1 and 100 nanometres (nm) in diameter. The term is sometimes used for larger particles, up to 500 nm, or fibers and tubes that are less than 10 ...

s 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 Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

could be used to deactivate the nanobots. Both techniques induce an electromagnetic field, corrupting the

memory Memory is the faculty of the mind by which data or information is encoded, stored, and retrieved when needed. It is the retention of information over time for the purpose of influencing future action. If past events could not be remembered ...

and shorting out the circuitry of any electronic device within range.

Amino acids

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. 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

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 Nucleotides are organic molecules consisting of a nucleoside and a phosphate. They serve as monomeric units of the nucleic acid polymers – deoxyribonucleic acid (DNA) and ribonucleic acid (RNA), both of which are essential biomolecules with ...

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. 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 In biology, cell signaling (cell signalling in British English) or cell communication is the ability of a cell to receive, process, and transmit signals with its environment and with itself. Cell signaling is a fundamental property of all cellula ...

. Synthetic proteins could be developed as a form of indicator and attached to a DNA-based nano-device. 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.

Programming

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. The “remote”-controlled nano-device would require a specialist in the room, to guide the nanobot throughout the procedure.

Cellular engineering

Many researchers are developing methods that use

bacteria Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...

to deliver drugs. These bacteria can be “programmed” to perform a specific task, and can be directed to go to targeted locations in the body.Cao, Guozhong. Nanostructures & Nanomaterials: Synthesis, Properties & Applications. London, UK: Imperial College Press, 2004. 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.

References

{{DEFAULTSORT:Fail-Safes In Nanotechnology Nanotechnology