Welcome to Biomedical Nanotechnology. In this module, we will define nano, nanotechnology and its importance, quantum effects, physical properties, and cellular structure.
WHAT IS NANO?
A nanometer is one billionth of a meter (10-9 meters)
So, how big, long, tall are we talking about?
- kilometer (km)- Height of a mountain
- meter (m)- Height of a human
- centimeter (cm)- An earthworm
- millimeter (mm)- A house flee
- micrometer (mm)- A human hair; red blood cell
- nanometer (nm)- virus, protein, atom, visible wavelength
The chart below illustrates the size comparisons of various objects.
What is nanotechnology?
Nanotechnology is the branch of engineering that deals with things smaller than 100 nanometers (especially with the manipulation of individual molecules). Some researchers refer to less than 1,000 nanometers. NIST defines nanotechnology as “research and technology development at the atomic, molecular or macromolecular levels, in the length scale of approximately 1-100 nm range, to provide a fundamental understanding of phenomena and materials at the nanoscale and to create and use structures, devices and systems that have novel properties and functions because of their small and /or intermediate size.”
What is unique about nanotechnology structures?
Now that we are operating at the nano-scale, material physical properties do not depend solely on its composition and structure. As a result three features dominate:
Topology- quantum rules apply, everything tends to be bumpy
Movement- thermal energy is produced since everything “moves and shakes”
Adhesiveness- intermolecular forces dominate since everything sticks together in the biological system
The laws of traditional physics no longer apply at the nano-scale. Nanomaterials display new phenomena associated with quantized effects and with the prevalence of surfaces and interfaces. The quantum effects lead to optical, electrical and magnetic behaviors different from those of the same material at a larger scale. This creates marvelous physical properties such as:
- exceptional electrical conduction or resistance
- the ability to store or transfer energy
- bioactivity modification
- unique mechanical, electronic, photonic, and magnetic
Nano-size materials exhibit the following physical properties:
- High surface to volume ratio (i.e. 3 nm particle has 50% atoms on the surface)
- Faster reactivity
- lower weight structures with improved strength and hardness, altered bending and compression properties
- Unique absorption and fluorescence (i.e. nanocrystals and nanoparticles)
- Improved flow properties (i.e. nanoparticles, nanoscale films)
- Increased thermoelectric performance (i.e. thermal resistance)
A cell is the unit of structure and function of which all plants and animals are composed. This machine is the smallest unit in the living organism that is capable of integrating the essential life processes. There are many unicellular organisms, such as bacteria and protozoans. These single cell machines functions in all life functions. In higher organisms, a division of labor has evolved in which groups of cells have differentiated into specialized tissues, which in turn are grouped into organs and organ systems.
The cellular components are very tiny, and are on the nano-scale. They are very active, manufacture various substances, walk around, wiggle, and do all kinds of unique things.
The picture below illustrates the various components of a the cellular structure, including the vesticle, Golgi, nucleus, etc.
Molecular diseases (such as cancer) and molecular machines (such as protein) function on the nano-scale. Example components and their dimensions include the following:
20 nm sphere
100 nm sphere
10 nm rod
4 nm sphere
7 nm sphere
- A minute round particle composed of RNA and protein that is found in the cytoplasm of living cells and serves as the site of assembly for polypeptides encoded by messenger RNA.
- Parasite with a noncellular structure composed mainly of nucleic acid within a protein coat.
- A pancreatic digestive enzyme that catalyzes the hydrolysis of certain proteins in the small intestine into polypeptides and amino acids.
Why is nanotechnology important?
Biomedical nanotechnology has the promise of curing cancer and wound healing through nanotechnology platforms such as drug delivery, tissue regeneration, bio-imaging, and bio-sensing.
The promise of curing cancer (for example) requires the manipulation of biological nano-size structures (such as cancer cells). Also, these technologies must be customized to only target the biological structures of interest.
This platform creates an emerging list of discoveries including:
This supplemental reading below summarizes research and findings regarding nanotech oversight, public awareness and attitudes, and work to develop a more strategic approach to addressing the potential risks associated with nanotech-based materials and products.
This supplemental reading below reviews nanoscience and nanotechnology applications.