Wednesday, July 23, 2014

Nanotechnology + Art | Week 5 Notes

Lecture 1 - Jim Gimzewski
- Dr. Gimzewski works in CNSI
- Nanotechology is a very broad field that applies to all of science. 1nm = 10^-9m
- Term originally used in 1974 by Norio Taniguchi to describe thin filaments
- Historical perspective of technology: two approaches. Electronic devices started out huge and have become smaller and smaller (top-down, hacking away at silicon). On the other hand, chemists began with very simple molecules and biochem/chem/physics are now becoming larger and larger.
- Richard Feynman's "There's Plenty of Room at the Bottom", suggested that there is so much room to make tiny things that you don't need to always think bigger is better.
- Quote: "The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom."
- To exemplify this, he wrote 25,000 pages of Encyclopedia Britannica on a pinhead (though a pinhead has room for 260,000,000 pages). Offered prizes for a small cubic electric motor 0.4mm in dimension and a book page shrunk by a factor of 25,000 in each direction (100nm font size), prizes claimed very soon after.
- Realization that nanoscale changes the laws of physics, as surface tension and thermal jittering dominate over gravity. Rules of quantum mechanics now dominate!
- Drexler & Merckle -- Foresight Organization, came up with the idea of an assembly plant on a molecular scale.

Lecture 2: Nanoparticle Imaging
- Breakthroughs: moving atoms on a single-atom basis, discovery of the Bucky Ball
- pre-1985, carbon had two allotropes, diamond and graphite. In 1986, Smalley, Curl, and Croto discovered another form of pure carbon (C60) - buckminsterfullerene
- 2011 Nobel Prize for Physics: graphene (carbon tubes, pure carbon)
- Scanning tunneling microscope (STM) - different because it doesn't use lenses (limits magnification due to wavelength of light). Rasters the STM tip across the surface to image molecules
- STM is great because you can resolve atoms in air, liquids, low temperatures, high temperatures, not just vacuums!
- Also able to create Tunable bonds between the tips and atoms of the surface of the molecule being imaged. Effect used to drag atoms across molecules --> UCLA dragged into formation!
- Quantum Corrals - fantastic patterned wave patterns
- Atomic Force Microscope (AFM)

Lecture 3: Nanoparticles + Applications
- 1-100nm
- Green cup, but if you illuminate from inside, it glows --> coloration from nanosized gold particles (Romans!)
- 15th & 16th century: glazes for plates, stained glass using nanoparticles
- Changing large scale --> nanoparticles changes a lot of physical properties (combustibility, state, etc.)
- Use of nanoparticle as biomimicry
- Ex. replicating the adhesive properties of gecko feet
- Ex. hydrophobicity creating isolated water droplets on surface of lotus leaves --> self-cleaning fabrics where materials will breathe but won't stick to particles (upholstery, self-cleaning glass, etc.)
- Ex. Japan's bullet train has self-cleaning surfaces to save energy on cleaning
- 1nm thick nanoclay - sheets of material added to plastics of beer bottles (to maintain carbonation)
 or surfaces of tennis balls (to reduce gas permeation)

Lecture 4: Nanomedicine
- Nanotechnology can target specific tumors, directed chemotherapy
- Abraxane - coating of nanoparticles in breast cancer medicine helps to reduce toxicity
- Color is dependent on size, so nanoparticles in solution can give off different hues based on size
- Nanotechnology products influential in pigment alteration, quantum dots
- If nanoparticles are smaller than 4nm, they can cross the blood-brain barrier and can be absorbed into cells via endocytosis
- Nanoshells (hollow nanoparticles), when it is illuminated, it becomes hot --> being tested in labs as cancer therapies, as these shells can be targeted via antigens to attack solely cancer cells

Lecture 5: Self-Assembly
- To create new structures atom-by-atom is not practical, we need to rely on self-organization into hierarchal structures (natural order)
- On Growth & Form (1945) -- fractal nature of trees, snowflakes, shells, etc.
- Blue Morpho Butterfly - extreme flash that can be seen from a mile in the air. Butterfly has christmas tree-like structures that manipulate light on the nanoscale so that they reflect back color much more effectively than pigments can do alone
- Ex. Formation of micelles due to hydrophobic principles
- Designing of 3D DNA crystals
- Nanosomes - created by finely tuning chemistry
- Nanotechnology can possibly self-assemble into organs or tissues
- Marangoni Effect

Lecture 6: Nanotechnology in Daily Life 

- 1,000 products, from food and agriculture to cosmetics
- Interactive, personalized foods --> allows for flavors to be individually released
- Nanowrappers, nanosensors
- Agroculture - coat pesticides so that they don't interact with plants but still protect from insects
- "Slim Shake Chocolate" - contains mostly silica nanoparticles that coat chocolate to trick you into thinking you're drinking a shake with lots of chocolate, because you're only tasting the coating



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