Nanomachines The Science of molecular size machines and its engineering designs and constructions until late 1980s were not considered practicable. Nanotechnology, according to the leading exponents of that time were neither feasible nor viable, due to the fact of total structural difference of the constituent of nano-molecular device i.e. Atoms from the mechanical objects of every day life. The essential components of engineering mechanics i.e. cogwheels, gears or motors could not be imagined to have formed by means of atoms, that are characterized by fuzzy and unsubstantial contents having no definite location position. Edwin Schrdinger, a leading quantum theoretician, regarded the particles as not permanent entity but an instantaneous event and derived the conclusion that atoms could no longer be regarded as "identifiable individuals." Werner Heisenberg, with extreme pessimism described atoms as "a world of potentialities or possibilities" rather than "of things and facts." (Is the future nano?)

Such ideologies succeeded making the scientists of that time convinced to view nanotechnology as an unattainable objective. During the second half of the 20th century some scientists however, ventured to explore the prospects of the subject. The efforts began with coinage of the terminology of molecular engineering by Arthur Von Hippel, an electric engineer of Massachussetts Institute of Technology (MIT) during 1950s and with his optimistic predictions for possibilities of the constructing nano-molecular devices. Contemporary Nobel laureate and physicist, Richard Feynman revolutionized the concept through his lecture "There is plenty of room at the bottom." (Is the future nano?) K. Eric Drexler, set up the organization "Foresight Institute, Palo Alto at California, in 1986 for popularization by the concept of building materials and products with atomic precision. Presently, scientists consider it as the pioneer organization for development of nanotechnology.

Questions still arise in the present scenario with regard to the progress of development of nano-technology. Even though much has been achieved in the field, the dreams have not yet been fulfilled till now. However, developments and intensive research in the field have given rise to revealing of new features of atoms, such as robustness of atoms to exist independently, facilitating isolation and counting in units. This feature of atoms gives strength to construct reliable parts of working nano devices. Currently, we have the capability to make the atoms move around so as to place them in desired locations. These achievements in less than past two decades have led to Nobel Prize winning contributions in the field. The remarkable contributions of Dehmelt of University of Washington in Seattle, revealing stability of even subatomic particles enabling its isolation within magnetic traps for months together is noteworthy. (Is the future nano?)

Table 1. Prizes for elucidating atoms and subatomic particles

Nobel prize

Winners

Achievement

Gerd Binnig, Heinrich Rohrer

Scanning tunnelling microscope

Hans Dehmelt, Wolfgang Paul

Traps to isolate atoms and subatomic species

George Charpak

Subatomic particle detectors

Clifford Schull,

Bertram Brockhouse

Neutron diffraction techniques for structure determination

Steven Chu,

Claude Cohen-Tannoudji,

William Phillips

Methods to cool and trap atoms with laser light

Source: Is the future nano?)

Devices constructed from individual atoms are called Nanomachines. According to some researchers; in future, to combat disease, nanomachines will be able to enter living cells. Nanomachines, which can reorganize atoms in order to make new objects, can be built in future, according to the researchers. Nanomachines, if the researchers succeed, can be used to get rid of poverty by obviously converting dirt into food. Nanomachines are incredibly small devices, as the terminology indicates. They are constructed from individual atoms and their size is measured in nanometers. (Nanomachines: Nanotechnology's Big Promise in a Small Package)

There is no macroscopic analogue for Nanomachine. By atomic scale "pick and place," nanomachine would make any structure, including itself, that is, a set of nanoscale pincers would pick individual atoms from their surroundings and place them where they should go. (Nanotechnology: Nanomachines) Futurist and visionary K. Eric Drexler made famous the capability of nanomachines during the 1980's and 1990's. K Eric Drexler coined the concept of nanotechnology during 1986, and made public in his publication of Engines of Creation. Drexler visualized the possibilities of efficient construction of objects at molecular level with the help of microscopic machines which were predicted to be the solutions for many ailments of the present world. (Book Review: Unbounding the Future: The Nanotechnology Revolution by K. Eric Drexler and Chris Peterson with Gayle...

The nanomachine assembler is intended to influence matter at the atomic level. The assembler will be used to move atoms from existing molecules into that of new structures and will be built with small 'pincers'. The idea is that the assembler should fabricate useful items from raw material by reorganizing atoms. If one can scoop dirt into a vat and be patient, a team of nanomachine assemblers can change the dirt into an apple, a chair, or even a computer, and this is the theory. A molecular schematic of the object to be built is to be put up into the memory of the machines in the vat. Then they would fabricate the chosen item by methodically rearranging the atoms enclosed in the dirt. (Nanomachines: Nanotechnology's Big Promise in a Small Package)
Though some primordial devices have been tested, Nanomachines are mainly in the phase of research development. A sensor with capability to count specific molecules in a chemical sample, and having switched approximately 1.5 nanometers across, is an example. Medical technology is the field where nanomachines will find applications firstly to recognize pathogens and toxins from the samples of body fluid. (Nanomachine) Nanomachines can be used in the field of pharmaceuticals, to watch over symptoms of change in a patient, to treat cancer, AIDS and to use it for operations of those areas which are difficult for operating upon. (The Ethics of Nanotchnology) It could be used to produce carbon fibers which would be as strong as Diamond and which also be less expensive than plastic. Also an important aspect of nanomachines is that this technology is comparatively less expensive, clean and also which is easy to maintain than other technologies which are presently available. (Book Review: Unbounding the Future: The Nanotechnology Revolution by K. Eric Drexler and Chris Peterson with Gayle Pergamit)

http://cseserv.engr.scu.edu/StudentWebPages/AChen/img/FigRes5BS.jpg

Respirocytes with Red Cells.

(by Vik Olliver, 1998)

The Ethics of Nanotechnology. Retrieved at http://cseserv.engr.scu.edu/StudentWebPages/AChen/ResearchPaper.htm

For decades, scientists' brains are filled with the development of nanomachines. The discovery of bio-molecular motors, such as myosin, kinesin and dynein, roughly 20 years ago, was the starting point for the dream of constructing machines which had the capacity to copy, replace or to work in recital with existing bio-molecular machines. The understanding of the biophysical and biochemical properties of bio-molecular motors have been enhanced by present day technologies which help to watch, influence and analyze particles or molecules at the nanometer scale. Proteins are the bio-molecular motors, which generate forces and movements within cells, that is, transforming chemical energy into mechanical energy. The diverse functions of these proteins are such that some are accountable for rotation and mobility of cilia, DNA replication, organelles transport, etc. (Bio-Molecular Motors Research in Japan: Asian Technology Information Program)

As an example, the mechanical activity of bio-molecular motors is sustained by the hydrolysis of ATP (adenosin-triphosphate), the "fuel," which turns out energy for the processive movement of kinesin along microtubes or the contraction of the actin/muosin complex in muscles. The purposes of bio-molecular machines cannot be read by equivalence to artificial machines, as they are not simple. Molecular machines and proteins have an active structure and have size in comparison to the nanometer range. Also, thermal energy can be matched up to the input energy to the molecular machines and when shown to thermal agitation, the molecular machines function at very high efficiency.

The artificial machines come in contrast with molecular machines, as artificial machines use much higher energy than thermal energy to work quickly, deterministically and precisely. Hence, on such grounds, an understanding of the dynamic properties of proteins and their interactions among themselves is essential. The development of Single-Molecule Detection (SMD) techniques to straightforwardly check the dynamics of proteins and molecular machines have been extended to encompass a wide variety of biological sciences. SMD techniques, in amalgamation with nanotechnology developments, will be more influential in directing more research in development of nanomachines and that of bio-molecular machines. (Bio-Molecular Motors Research in Japan: Asian Technology Information Program)

These machines mostly consist of proteins which are synthesized out of carbon- the chief ingredient of all living things. And as Drexler explained, these machines, called as assemblers, will be built on the basis of one atom at a time, with the capacity of being able to fit several hundreds within a single cell. That these man-made nano-assemblers will add innumerable variety to the countless life forms that are currently known is agreed from both sides of the debate. This is due to a number of appealing differences between the assemblers and the biological cells on which they are based. The replication instructions within these hybrid biological/mechanical machines to be designed by engineers will be composed of computer code instead of DNA is one such difference worth…