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N. Ponpandian – BU-NST Bharathiar University Coimbatore Nanostructures and its Applications N. Ponpandian Department of Nanoscience and Technology Bharathiar University Coimbatore 641 046 Email: [email protected] Web: http://www.bunst.org 1 of xx N. Ponpandian – BU-NST ELECTRON WAVES Separate NanoSCIENCE from MicroSCIENCE Bharathiar University Coimbatore The discovery that electrons = waves led to QUANTUM MECHANICS A weird, new, counter intuitive, non-Newtonian way of looking at the nano world With a particular impact upon our understanding of electrons: Electrons => Waves How do you figure out an electron’s wavelength? electron = h / p “De Broglie’s Relationship” ( = electron wavelength, h = Planck’s Constant, p = electron’s momentum) This relationship was based on series of experiments late 1800’s / early 1900’s 2 To put the size of an electron’s wavelength in perspective: 2 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 3 3 of xx N. Ponpandian – BU-NST How to see the Nanoparticles? 4 of xx Size of Things (red = man-made things) N. Ponpandian – BU-NST Millimeters Ball of a ball point pen Thickness of paper Human hair Talcum Powder Fiberglass fibers Carbon fiber Human red blood cell E-coli bacterium Size of a modern transistor Size of Smallpox virus 0.5 0.1 0.02 - 0.2 Bharathiar University Coimbatore Microns Nanometers 100 20 – 200 40 10 5 4–6 1 0.25 0.2 – 0.3 250 200 – 300 ___________________________________________________________________________________________________ Electron wavelength: ~10 nm or less Diameter of Carbon Nanotube Diameter of DNA spiral Diameter of C60 Buckyball Diameter of Benzene ring Size of one Atom 3 2 0.7 0.28 ~0.1 5 of xx 2a N. Ponpandian – BU-NST Bharathiar University Coimbatore a a a A = 4 x 2 a x a + 2 a2 = 8 a2 + 2 a2 = 10 a2 A = 6 x a x a + 6 a x a = 12 a2 6 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 7 of xx 8 of xx N. Ponpandian – BU-NST N. Ponpandian – BU-NST Bharathiar University Coimbatore 9 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 10 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 11 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 12 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 13 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 14 of xx Bharathiar University Coimbatore N. Ponpandian – BU-NST Types of materials 1. Metals – No band gap 2. Semiconductors – low band gap 3. Insulators – very high band gap 15 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore • Quantum dots are nanocrystals of semiconductors that exhibit quantum confinement effects, once their dimensions get smaller than a characteristic length, called the Bohr’s radius. • This Bohr’s radius is a specific property of an individual semiconductor • Bohr’s radius can be equated with the electron–hole distance in an exciton that might be formed in the bulk semiconductor. 16 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore • Below this length scale (Bohr’s radius) the band gap (the gap between the electron occupied energy level, similar to HOMO, and the empty level, similar to LUMO), which are is size-dependent. • Band gap is Size Dependent Conduction band Valence band 17 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Structural differences Nanoscale Carbon Bulk Carbon C60 (Buckeyball) Smalley, Curl, Kroto 1996 Nobel Prize Graphite Diamond Carbon Nanotubes Sumio Iijima - 1991 18 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 19 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 20 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 21 of xx N. Ponpandian – BU-NST Fe filled MWCNT: Bio-compatible nanomagnets Bharathiar University Coimbatore 22 of xx N. Ponpandian – BU-NST Fe filled MWCNT: Bio-compatible nanomagnets Bharathiar University Coimbatore 23 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 24 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 25 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 26 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 27 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 28 of xx 29 of xx N. Ponpandian – BU-NST Why nanocrystalline materials t of have excellent soft magnetic properties N. Ponpandian – BU-NST Lex ? D AK1 H c pc Js D Random Anisotropy Model 2 AK Grain size > exchange length 41 6 J D AK K D s 1 H 1 H pp Hcc ppc c J D soft magnetic properties as grain size c c i 3 AK s Js A 0J s D 1 J s2 4D 6 J s2 A3 Grain size < exchange length p K1 D Hi pc AK3 p as grain size 4 6 soft magnetic properties 0 c Js A 1 i 0 K1 D 30 30 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 31 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Response of superparamagnets to applied field described by Langevin model Qualitatively paramagnets At room temperature superparamagnetic materials have a much greater magnetic susceptibility per atom than paramagnetic materials similar to 32 of xx 33 of xx N. Ponpandian – BU-NST N. Ponpandian – BU-NST Bharathiar University Coimbatore • Iron and living things Many animals use magnetic fields to navigate Synthesize hemoglobin Role of iron in neurodegenerative disease • Medical applications Removal of iron splinters, shrapnel, etc. Holding prosthetics Guiding instruments through the body MRI 34 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore • Magnetic imaging • Magnetic heating (Hyperthermia) • Targeted drug delivery • Detection/purification/isolation • Manipulation 35 of xx N. Ponpandian – BU -NST Goal: Separate/detect/isolate one type of cell from others, often when the target is present in very small quantities Bharathiar University Coimbatore N. Ponpandian – BU-NST Functionalized nanoparticles O R O- O- O Ligand 37 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Cells 38 of xx Bharathiar University Coimbatore N. Ponpandian – BU-NST Magnetic nanoparticles bond with targeted cells 39 of xx Bharathiar University Coimbatore N. Ponpandian – BU-NST Retain desired cells by applying a magnetic field 40 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore • Cancer cell growth is slowed or stopped at 42 °C - 46 °C • Magnetic materials inside the body generate heat due to • Hysteresis • Brownian motion • Eddy currents • Nanoparticles provide • uniform heating • non-invasive delivery • multiple treatments • Human clinical trials in progress (Germany) 41 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 42 of xx N. Ponpandian – BU-NST Magnetic resonance imaging Bharathiar University Coimbatore Non-invasive method used to render images of the inside of an object Primarily used in medical imaging to demonstrate pathological or other physiological alterations of living tissues MRI is currently the most efficient imaging procedure used in medicine 43 of xx N. Ponpandian – BU-NST Typical MRI device Bharathiar University Coimbatore 44 of xx N. Ponpandian – BU-NST Typical MRI images Bharathiar University Coimbatore 45 of xx N. Ponpandian – BU-NST Problems in MRI Bharathiar University Coimbatore Low contrast between different tissues Low contrast between a healthy tissue and tumors 46 of xx N. Ponpandian – BU-NST Contrast agents Bharathiar University Coimbatore Different contrast agents are administered in 40–50% of all MR examinations in order to improve the efficiency of this procedure Contrast agents are diagnostic pharmaceutical compounds containing paramagnetic or superparamagnetic metal ions or nanoparticles that affect the MR-signal properties of surrounding tissues Gadolinium chelates are the most widely used extracellular, non-specific contrast agents Organ specific contrast agents include superparamagnetic iron oxides nanoparticles stabilized with appropriate biopolymers or biocompatible synthetic polymers 47 of xx N. Ponpandian – BU-NST Clinically approved superparamagnetic contrast agents stabilized with biopolymers Bharathiar University Coimbatore Ferumoxide (Endorem, Feridex) dextran stabilized Ferumoxtran (Sinerem, Combidex) dextran stabilized Ferucarbotranum (Resovist) carboxydextran stabilized Used for intravenous applications 48 of xx N. Ponpandian – BU-NST MRI of liver tumor Bharathiar University Coimbatore After SPIO application Normal liver tissue contains phagocytic Kupffer cells darkening after dextran-coated SPIO application Cancer cells do not contain Kupffer cells after dextrancoated SPIO application tumor is brighter that surrounding tissue Before SPIO application 49 of xx MRI of gastrointestinal tract Bharathiar University Coimbatore N. Ponpandian – BU-NST Oral application of superparamagnetic nanoparticles Small bowel before (left) and after (right) application of the oral50 of xx N. Ponpandian – BU-NST MRI of gastrointestinal tract Bharathiar University Coimbatore Commercially available contrast agents: Ferumoxsil (GastroMARK, Lumirem) silicon-coated superparamagnetic iron oxide Ferristene (Abdoscan) sulphonated styrenedivinylbenzene latex particles (Ø 3.5 μm) with bound superparamagnetic nanoparticles 51 of xx N. Ponpandian – BU -NST N. Ponpandian – BU-NST Bharathiar University Coimbatore 53 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Nanomedicine is an interdisciplinary field of science, even a simple project needs contributions from physicists, engineers, material chemists, biologists and end users, such as an orthopaedic surgeon. A mature nanomedicine will require the ability to build structures and devices to atomic precision, hence molecular nanotechnology and molecular manufacturing are key enabling technologies for nanomedicine. Medicine must catch up with the technology level of the human body before it can become really effective. The result will be the ability to analyse and repair the human body as completely as we can repair a conventional machine today. If the nanoconcept holds together, it could be the groundwork for a new industrial revolution. BUT: can all different scientists and engineers work together to achieve crossover dreams? 54 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Despite the importance of nanotechnology, literature review of robotics in 1993 included not a single reference to nanotechnology or nanomedicine. The first nanomedical device design technical paper in 1998 by Freitas: Respirocyte – an Artificial Red Cell. 55 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Nature has created nanostuctures for billenia. Biological systems are an existing proof of molecular nanotechnology. Biology is an ingenious form of nanotechnology, even very simple living cells are able to duplicate. So far there is no machine of any size or type, which could do the same. 56 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Replication is a basic capability for molecular manufacturing. Still some scientists think that medical nanorobots need not ever replicate. It is unlikely that the FDA would ever approve a use of a medical nanodevice that was capable of in vivo replication. Replicators will be very tightly regulated by governments everywhere. In practice you would not want anything that could replicate itself to be turned loose inside your body. 57 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Nanomedicine will eliminate virtually all common diseases, all medical pain and suffering => theoretically eternal life. Extension of human capabilities. Pollution-free industry will guarantee the well-being for the nature. New era of peace. People who are well-fed, well-clothed, welleducated, healthy and happy will have little motivation to make war. 58 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Self replicating nanorobots could become massive chemical and biological weapons. Changes to human properties, such as brains, respiration, muscles and DNA will be uncontrolled and may threat the existence of human being. 59 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 60 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 61 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Nanoparticles can deliver drugs in a sophisticated ways, like target specific and trigger based drug dose. Target specific delivery enables the use of lower doses, because the whole body is not saturated with the drug. The side effects will be minimized, and it is possible to use stronger drugs, which could not be used by conventional drug delivery. The use of gold particles in cancer healing is an example target specific action. Gold plated spheres are linked to tumor cells. Nanoshells can be heated from the outside using an infrared source. Heating the shells destroy the cancerous cells, leaving the surrounding tissue unharmed. 62 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Using magnetic nano particle can Improve imaging with better contrast agents and helps to diagnose diseases more sensitively. The method enables the detection of very small tumors and other organisms which cause disease. When the diagnostics is improved the healing will also be easier. 63 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Semiconductor nanocrystals, quantum dots, absorb only photons of light omitting just the right wavelength for their size. Use of a variety of sizes and concentrations of quantum dots produces a spectral bar code with distinct spectral lines. Such method allows multiple labels. Fast and accurate DNA testing, comparison of genetic material, rewriting DNA sequences in vivo, and even home DNA test systems. 64 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore SurroMed company is developing nanobarcode® technique with researchers from the Penn State University. The idea is to use little metallic bars. Consecutively alternating gold- and silver-bands on a bar are interpreted as individual bits. Twenty bands equal twenty bits ≈ 106 alternatives. The bands can be interpreted with an optical microscope. 65 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Numerous DNA-testers can be attached to a single bar, the testers combine with receptor molecules. The complex formation results a multiple DNA-sequence analysis. Also antibody molecules can be attached to a surface of a bar, after an immunologic reaction peptide hormones can be analysed. Hundreds of components can be measured from one milliliter of serum, multiple test tubes and plentiful blood samples become unnecessary. 66 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore The connection between implant material and bone/ surrounding tissues is a key factor to a successful and long-term use of prostheses. Nano-scale modifications of implant surfaces would improve implant durability and biocompatibility. 67 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Teeth cleaning robots collect harmful bacteria from the mouth. 68 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Similar cleaning robots can be used in lungs. We have natural macrophages in alveoli, but they are not able to metabolize foreign particles like fibers of asbestos and toxic effects of smoking from the lungs. 69 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Extra fat can be removed from the arteries with cleaning robots. 70 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore It is an artificial mechanical red blood cell floating along in the bloodstream. A spherical (d = 1 μm) nanomedical device is made of 18*109 atoms (mostly carbon). The design of respirocyte was the first technical paper on nanomedical device design. It was published in 1998 by Robert A. Freitas. It is important to notice that molecular nanotechnology violates no physical laws and there are technical paths leading to useful results. Respirocyte device cannot be built today 71 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore A nanostructured data storage device measuring a volume about the size of a single human liver cell can store an amount of information equivalent to the entire library. 72 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Researchers hope to figure out ways to regenerate skin, bone and more sophisticated organs. At present auto-, allo- and xenografts plus some artificial materials are being used for reconstruction of damaged tissues and organs. The amount of auto- and allografts is limited, and allo- and xenografts carry a risk of infection (HIV or BSE). So the need and interest for artificial regeneration definitely exists! 73 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore Shape and size Biocompatibility Powering Communication Navigation 74 of xx N. Ponpandian – BU -NST N. Ponpandian – BU-NST Bharathiar University Coimbatore 76 Albert Fert Université Paris-Sud Unité Mixte de Physique CNRS/THALES Orsay, France Peter Grünberg Forschungszentrum Jülich Jülich, Germany 76 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 77 77 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 78 78 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 79 FM 2 FM 1 79 of xx N. Ponpandian – BU-NST Bharathiar University Coimbatore 80 80 of xx N. 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