Nanotechnology Muhammad Awais Afzal 12-10463 Medical Biotech What is Nanotechnology • The prefix “nano”is a Greek word for “dwarf” • One nanometer (nm) is equal to one-billionth of a meter • About a width of 6 carbon atoms or 10 water molecules • A human hair is approximately 80,000 nm wide • Red blood cells is 7000 nm wide • Atoms are smaller than 1 nanometer • Molecules and some proteins are between 1 nm and above • Intentional design, characterization, production and application of materials, structures, devices and systems by controlling their size, and shape in the nano-scale range (10 - 100nm) • Production of matter at the nano scale in order to create materials, devices and systems with fundamentally new properties and functions Properties • Two nanoparticles of different size, both made of pure gold, can exhibit – different melting temperature – different electrical conductivity – different color Nanotechnology New way to control the properties of materials Change size…..instead of changing composition Nanomedicine • Research on biosystems at the nanoscale has created one of the most dynamic science and technology domains at the confluence of physical sciences, molecular engineering, biology, biotechnology, and medicine Nanomedicine •Most the diseases originate from alterations in biological process at the molecular or nano-scale levels •Mutated genes, mis-folded proteins and infections caused by viruses or bacteria lead to cell malfunction or miscommunication, sometimes leading to lifethreatening diseases. These molecules and infectious materials are nanometer in size and may be located in biological systems that are protected by nanometer size barriers such as nuclear pores 9nm in diameter Nanomedicine • The field of nanomedicine aims to use the properties and physical characteristics of nanomaterials for the diagnosis and treatment of diseases at molecular levels • Because nanomaterials are similar in scale to biologic molecules and systems yet can be engineered to have various functions, nanotechnology is potentially useful for medical applications Nanomaterials • The surface of nano-materials is usually coated with polymers of bio-recognition molecules for improved biocompatibility and selective targeting of biologic molecules Application of Nanotechnology in Medicine Diagnostic - Imaging - Quantum dots - Microscopic sampling - Detection of airway abnormalities Therapeutic -Delivering medication to the exact location -Killing of bacteria, viruses & cancer cells -Repair of damaged tissues -Oxygen transport -Skin and dental care -Augmentation of immune system -Treatment of Atherosclerosis Diagnostic Applications of Nanotechnology in Medicine • Improved imaging of the human (or any) body • Nanoprobes (miniature machines) can attach themselves to particles in the body (e.g., antibodies) and emit a magnetic field. • Probes that aren’t attached to anything don’t create a detectable magnetic • Nano-tracking may be able to detect tumors that are a few cells in size Diagnostic Applications of Nanotechnology in Medicine • Another way to use nanotech as tracking devices is to use “quantum dots” • These tiny semiconductors are able to emit wavelengths of light (colors) that depend on their size. If quantum dot A is twice as big as quantum dot B, it will emit a different color. • Quantum dots are better than conventional dyes: – They last much longer – More colors can be made available. • “A microscopic machine roaming through the bloodstream, injecting or taking samples for identification and determining the concentrations of different compounds" Therapeutic Applications of Nanotechnology in Medicine • Nanotech is capable of delivering medication to the exact location where they are needed – hence lesser side effects –Organic dendrimers - a type of artificial molecule roughly the size of a proteinwould be ideal for the job of delivering medicine Therapeutic Applications of Nanotechnology in Medicine • Destruction of harmful eukaryotic organisms / cancer cells by interrupting their division process –Certain proteins are capable of doing this (e.g., Bc12 family of proteins) Therapeutic Applications of Nanotechnology in Medicine • Nanoprobe can be made to generate radiation, that could kill bacteria, viruses and cancer cells • Nanoprobe comprising of a single caged actinium-225 atom would detect (using antibodies) and enter a cancerous cell • Location and destruction of cancer cells by acoustic signals Cancer cell Lethal holes A CYTOTOXIC T CELL DESTROYING A CANCER CELL Cytotoxic T cell Therapeutic Applications of Nanotechnology in Medicine • Nanotechnology also theoretically allows the mimicking of natural biological processes e.g., repair of damaged tissues – Using nanotech to build scaffoldings of artificial molecules that bone cells often adhere to and grow bones on – Broken bones would heal much faster. • Transport of oxygen within the body by creating an artificial red blood cell Therapeutic Applications of Nanotechnology in Medicine To cure skin diseases, a cream containing nanorobots may be used it may: - Remove the right amount of dead skin - Remove excess oils - Add missing oils - Apply the right amounts of natural moisturising compounds - Achieve the elusive goal of 'deep pore cleaning' by actually reaching down into pores and cleaning them out. Therapeutic Applications of Nanotechnology in Medicine A mouthwash full of smart nanomachines could identify and destroy pathogenic bacteria while allowing the harmless flora of the mouth to flourish in a healthy ecosystem Dental Robots Four remote-controlled nanorobots examine and clean the subocclusal surfaces of a patient's teeth, near the gumline. Therapeutic Applications of Nanotechnology in Medicine Medical nanodevices could augment the immune system by finding and disabling unwanted bacteria and viruses. Virus Finder Therapeutic Applications of Nanotechnology in Medicine Devices working in the bloodstream could nibble away at atherosclerotic deposits, widening the affected blood vessels. This would prevent most heart attacks A NANOROBOT NIBBLING ON AN ATHEROSCLEROTIC DEPOSIT IN A BLOOD VESSEL NANOTECHNOLOGY • GOALS • Construction of a nano-assembler – A machine capable of building nanoprobes on a grand scale • The next step would be self-replication of nanoprobes- mitosis • Rough estimates say that this will be reached in about 10-20 years But There are many risks too Nanotoxicity Nanotoxicology is the study of the toxicity of nanomaterials Nanomaterials, even when made of inert elements like gold, become highly active at nanometer dimensions For example: Diesel nanoparticles have been found to damage the cardiovascular system in a mouse model (http://www.bloomberg.com/apps/news?pid=washington story&sid=aBt.yLf.YfOo) • Andrew Maynard (Nanotechnology: A Research Strategy for Addressing Risks. p. 310.)  Reports that ‘certain nanoparticles may move easily into sensitive lung tissues after inhalation, and cause damage that can lead to chronic breathing problems • The behavior of nanoparticles is a function of their size, shape and surface reactivity with the surrounding tissue • In principle, a large number of particles could overload the body's phagocytes that lead to inflammation and weaken the body’s defense against other pathogens • what happens if non-degradable or slowly degradable nanoparticles accumulate in bodily organs • Because of their large surface area, nanoparticles will , immediately adsorb onto their surface some of the macromolecules they encounter thus affecting the regulatory mechanisms of enzymes and other protein • They can have access to blood stream via inhalation, ingestion and even some nanoparticles can penetrate into the skin • Nanomaterials have proved toxic to human tissue and cell cultures, resulting in increased oxidative stress, inflammatory cytokine production and cell death (Oberdörster, Günter; et al. (2005). • Can cause DNA mutation and induce major structural damage to mitochondria, even resulting in cell death (Geiser, Marianne; et al. (November 2005) Thank You