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• “Nanostructures” are the smallest solid things it is possible to make and are
described as being at the confluence of the smallest of human-made devices and
the largest molecules of living things.
• “Nanotechnology” is the application of these nanostructures into useful
nanoscale devices.
• “Nanoscale” is the natural scale of all fundamental life processes and the scale at
which diseases need to be met and conquered.
• “Molecular nanotechnology” has been defined as the three-dimensional posi-
tional control of molecular structure to create materials and devices to molecular
precision.
• “Nanomedicine” is a science designed to employ molecular machine systems to
address medical problems, and will use molecular knowledge to maintain and
improve human health at the molecular scale.6
Mechanism of Action
Nanotechnology and biology share many similarities. The most complicated organisms
are made up of tiny cells, which are constructed from nanoscale building blocks: proteins,
lipids, nucleic acids and other complex biological molecules.7 Nanotechnology utilizes
tiny nanostructures made from semiconductors, metals, plastic or glass. At the nanoscale,
materials behave differently. Increased reactivity is one such property, a function of the
increased ratio of an object’s surface area to its volume as it gets smaller. Nanoparticles
of silver, for example, are more reactive than large particles. Platinum used for catalytic
converters removes pollutants from auto exhaust far more efficiently as nanoparticles.
Drug development is a nanoscale activity. Some of the largest and most important
categories of drugs are those that work by interacting specifically with DNA or proteins
in the body. This class of drug molecules includes aspirin, Cisplatin and other anti-cancer
agents as well as much more complex molecules like beta-blockers, anti-inflammatory
agents, antidepressants and compounds used in AIDS therapy.8
Drug Delivery
The major requirement for implantable drug delivery devices is controlled release of
therapeutic agents as a continuous process over an extended period of time. The goal is
to achieve a continuous drug release profile consistent with zero order kinetics where the
drug concentration remains constant throughout the delivery period.9 Injectable drugs
display first order kinetics, in that there is an initially high concentration in plasma above
the therapeutic range, followed by an exponential fall in concentration. Toxicity occurs
when the peak concentration is above the therapeutic range, while drug efficacy dimin-
ishes as the drug concentration falls below this range. Drug delivery systems with a zero
order release rate have several potential therapeutic advantages including: in vivo release
rate predictability on the basis of in vitro data, minimized peak plasma levels and, thereby,
reduced risk of adverse reactions predictable and extended duration of action reduced
inconvenience of frequent redosing and improved patient compliance.10 Controlled drug
delivery systems should thus be aimed at improved drug treatment outcome through
rate and time programming and site-specific targeting. Nanotechnology now provides
the means to achieve this goal. New technologies like molecular modeling, combinato-
rial chemistry, high throughput screening and bioinformatics are the engineering tools
of the future. According to one researcher, “future categories of medicinal treatment will
comprise the following: mechanism-based small molecules (with several new classes of
medicines) therapeutic proteins and other macromolecules gene regulating medicines
and gene therapy.”11
Nanotechnology
• “Nanostructures” are the smallest solid things it is possible to make and are
described as being at the confluence of the smallest of human-made devices and
the largest molecules of living things.
• “Nanotechnology” is the application of these nanostructures into useful
nanoscale devices.
• “Nanoscale” is the natural scale of all fundamental life processes and the scale at
which diseases need to be met and conquered.
• “Molecular nanotechnology” has been defined as the three-dimensional posi-
tional control of molecular structure to create materials and devices to molecular
precision.
• “Nanomedicine” is a science designed to employ molecular machine systems to
address medical problems, and will use molecular knowledge to maintain and
improve human health at the molecular scale.6
Mechanism of Action
Nanotechnology and biology share many similarities. The most complicated organisms
are made up of tiny cells, which are constructed from nanoscale building blocks: proteins,
lipids, nucleic acids and other complex biological molecules.7 Nanotechnology utilizes
tiny nanostructures made from semiconductors, metals, plastic or glass. At the nanoscale,
materials behave differently. Increased reactivity is one such property, a function of the
increased ratio of an object’s surface area to its volume as it gets smaller. Nanoparticles
of silver, for example, are more reactive than large particles. Platinum used for catalytic
converters removes pollutants from auto exhaust far more efficiently as nanoparticles.
Drug development is a nanoscale activity. Some of the largest and most important
categories of drugs are those that work by interacting specifically with DNA or proteins
in the body. This class of drug molecules includes aspirin, Cisplatin and other anti-cancer
agents as well as much more complex molecules like beta-blockers, anti-inflammatory
agents, antidepressants and compounds used in AIDS therapy.8
Drug Delivery
The major requirement for implantable drug delivery devices is controlled release of
therapeutic agents as a continuous process over an extended period of time. The goal is
to achieve a continuous drug release profile consistent with zero order kinetics where the
drug concentration remains constant throughout the delivery period.9 Injectable drugs
display first order kinetics, in that there is an initially high concentration in plasma above
the therapeutic range, followed by an exponential fall in concentration. Toxicity occurs
when the peak concentration is above the therapeutic range, while drug efficacy dimin-
ishes as the drug concentration falls below this range. Drug delivery systems with a zero
order release rate have several potential therapeutic advantages including: in vivo release
rate predictability on the basis of in vitro data, minimized peak plasma levels and, thereby,
reduced risk of adverse reactions predictable and extended duration of action reduced
inconvenience of frequent redosing and improved patient compliance.10 Controlled drug
delivery systems should thus be aimed at improved drug treatment outcome through
rate and time programming and site-specific targeting. Nanotechnology now provides
the means to achieve this goal. New technologies like molecular modeling, combinato-
rial chemistry, high throughput screening and bioinformatics are the engineering tools
of the future. According to one researcher, “future categories of medicinal treatment will
comprise the following: mechanism-based small molecules (with several new classes of
medicines) therapeutic proteins and other macromolecules gene regulating medicines
and gene therapy.”11
Nanotechnology