Bio-Nanotechnology

1. BME 4215 Bio-Nanotechnology Dr. Md. Sherajul Islam Professor Department of Electrical and Electronic Engineering Khulna University of Engineering & Technology Khulna, Bangladesh

2. LECTURE - 1 Basic Concepts on Nanotechnology

4. Two Challenges by Feynman At the meeting Feynman concluded his talk with two challenges, and he offered a prize of $1000 for the first individuals to solve each one The second challenge involved the possibility of scaling down letters small enough so as to be able to fit the entire Encyclopædia Britannica on the head of a pin, by writing the information from a book page on a surface 1/25,000 smaller in linear scale First challenge involved the construction of a tiny motor A Nanometer is a molecular or nanoscale device capable of converting energy into movement In 1985, Tom Newman, a Stanford graduate student, successfully reduced the first paragraph of A Tale of Two Cities by 1/25,000, and collected the second Feynman prize Kinesin uses protein domain dynamics on nanoscales to walk along a microtubule.

6. Nanoscale

7. Nanoscale A sheet of paper is about 100,000 nanometers thick, a human hair is around 80,000- 100,000 nanometers wide 6,000 and 10,000 nanometers in diameter

8. Nanotechnology The art and science of manipulating and rearranging individual atoms and molecules to create useful materials, devices, and systems Nanotechnologyis defined as the knowledge and management of processes on a scale from 1 to 100 nm and application of object properties on a nanometer scale. Definition for the term nanotechnology was given for the first time by Norio Taniguchi, a professor of Tokyo University, in 1974 in his paper Basic concepts of Nanotechnology, which mentioned “Nanotechnology mainly consists of the processing of separation, consolidation, and deformation of materials by one atom or one molecule.”

9. Size Effects -Why does size influence the material’s properties? -How does size influence the material’s performance? -Why are properties of nanoscale objects differentthan those of the same materials at the bulk scale? -Why nanomaterials are unstable?

10. Size-dependent properties At the nanometer scale, properties become size-dependentFor example, (1) Chemical properties – reactivity, catalysis(2) Thermal properties – melting temperature(3) Mechanical properties – adhesion, capillary forces(4) Optical properties – absorption and scattering of light(5) Electrical properties – tunneling current(6) Magnetic properties – superparamagnetic effect New properties enable new applications !!!!!!

11. Scale Changes Everything Four important ways in which nanoscale materials may differ from macroscale materials – Gravitational forces become negligible and electromagnetic forces dominate– Quantum mechanics is the model used to describe motion and energy instead of the classical mechanics model– Greater surface area to volume ratios– Random molecular motion becomes more important

12. Dominance of Electromagnetic Forces Because the mass of nanoscale objects is so small, gravity becomes negligible – Gravitational force is a function of mass and distance and is weak between (low-mass) nanosized particles – Electromagnetic force is a function of charge and distance is not affected by mass, so it can be very strong even when we have nanosized particles The electromagnetic force between two protons is 1036 times stronger than the gravitational force!

13. Quantum Effects Classical mechanical models that we use to understand matter at the macroscale break down for… –The very small (nanoscale) –The very fast (near the speed of light) Quantum mechanics better describes phenomena that classical physics cannot, like… –The colors of nanogold –The probability (instead of certainty)of where an electron will be found

15. Surface Area to Volume Ratio Increases As surface area to volume ratio increases – A greater amount of a substance comes in contact with surrounding material – This results in better catalysts, since a greater proportion of the material is exposed for potential reaction

16. Random Molecular Motion is Significant • Tiny particles (like dust) move about randomly – At the macroscale, we barely see movement, or why it moves – At the nanoscale, the particle ismoving wildly, batted about bysmaller particles • Analogy – Imagine a huge (10 meter) balloon being batted about by the crowd in a stadium. From an airplane, you barely see movement or people hitting it; close up you see the balloon moving wildly

17. What Does This All Mean? The following factors are key for understandingnanoscale-related properties – Dominance of electromagnetic forces– Importance of quantum mechanical models– Higher surface area to volume ratio– Random (Brownian) motion It is important to understand these four factors when researching new materials and properties

32. What is nanomaterial? • Is defined as any material that has unique or novel properties, due to the nanoscale ( nano meter- scale) structuring. • These are formed by incorporation or structuring of nanoparticles. • They are subdivided into nanocrystals, nanopowders, and nanotubes: A sequence of nanoscale of C60 atoms arranged in a long thin cylindrical structure.

33. What is nanomaterial? carbon nanotubes

34. What is nanomaterial? Noble metal nanocrystals with cyclic penta-twinned structures

35. What is nanomaterial? Naonpowder

36. Types of nanomaterials • Nanomaterials can… • occur naturally • be produced by human activity either as a product of another activity • on purpose (engineered) • Our focus: engineered nanomaterials as these are designed and integrated into products because of the specific characteristics of the nanomaterial

37. Classes of nanomaterials

38. NanoZnO – One Chemistry, Many Shapes Courtesy of Prof. Z.L. Wang, Georgia Tech

39. Why are nanomaterials used? • At nano-scale, • the material properties change - melting point, fluorescence, electrical conductivity, and chemical reactivity • Surface size is larger so a greater amount of the material comes into contact with surrounding materials and increases reactivity • Nanomaterial properties can be ‘tuned’ by varying the size of the particle (e.g. changing the fluorescence colour so a particle can be identified) • Their complexity offers a variety of functions to products

40. Examples of nanomaterials in products • Examples: • Amorphous silica fume (nano-silica) in Ultra High Performance Concrete – this silica is normally thought to have the same human risk factors as non‐nano non‐toxic silica dust • Nano platinum or palladium in vehicle catalytic converters - higher surface area to volume of particle gives increased reactivity and therefore increased efficiency • Crystalline silica fume is used as an additive in paints or coatings, giving e.g. self-cleaning characteristics– it has a needle-like structure and sharp edges so is very toxic and is known to cause silicosis upon occupational exposure

41. Nanotechnology spans many Areas Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Information Technology Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Eng. & Robotics Mechanical Engineering / Robotics Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Biotechnology Transportation Transportation Transportation Transportation Advance Materials & Textiles Advance Materials & Textiles Advance Materials & Textiles Advance Materials & Textiles Advance Materials & Textiles NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY NANOTECHNOLOGY National Security & Defense National Security & Defense National Security & Defense National Security & Defense National Security & Defense National Security & Defense Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Energy & Environment Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Food and Agriculture Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Medicine / Health Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace Aerospace

42. Applications of Nanotechnology:General Applications

43. Environmental ApplicationsCheck http://www.nanowerk.com/products/product.php?id=160 for more details