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Nanobiotechnology and its Applications Chris Wright Nick D’Souza Kyle Ramirez What is Nanobiotechnology? Biotechnology is the application of technological innovation as it pertains to biological and life sciences. Nanobiotechnology incorporates biotechnology on the nano-scale. Introduction Size Ranges of Biological Material • Cells: 100um – 10um • Cell organelles (nucleus, mitochondrion): 10um – 1um • Viruses: 100nm- 50nm • Cell material (proteins, lipids, DNA, RNA): 10nm – 0.1nm Introduction Nanobiotechnology is an emerging field • cells discovered 1665 • electron microscope 1950s • Watson and Crick discover DNA double helix 1953 • Mapping of Human Genome 2003 Where is nanobiotechnology going? Applications? • • • • • • • • Cell structure and physiology Virus Detection Radiation/Chemotherapy Drug delivery Neurological functions of the brain Biomedical engineering research Study of molecular behavior Utilization of imaging devices http://www.jnanobiotechnology.com/home Brain-Machine Interface Brain-machine interface (BMI) is a fabricated system to interpret voluntary brain activity and convert to a mechanical movement • Physiology: Electrical signals in brain → spinal cord → skeletal muscle • BMI needed for individuals with: spinal cord injury, or Parkinson’s disease Brain-Machine Interface Procedures involved: 1) mapping of brain target specific neurons 2) electrode implantation 3) signal acquisition 4) wireless transmission 5) signal processing 6) mechanical action Study of DNA • DNA molecules, under the influence of an electric field, are forced through nano-scale channels (~100 nm) on a “gel biochip”. The molecules deform and stretch to pass through the small channels. • This process separates DNA fragments by length. This is part of the method used to sequence the DNA in the human genome and in identifying a unique DNA “fingerprint”. Nanomechanical Oscillator • A nano-scale cantilevered beam can be used to detect the presence of viruses and bacteria and find their masses. • The beam can be coated with antibodies specific to a particular virus and then put into a substance to attract that virus. The oscillation of the beam can then be measured and compared to the oscillation before exposure to the substance. http://www.hgc.cornell.edu/biomems.html Problem A nano-scale cantilevered beam is placed in a solution, which is known to contain E. coli bacterium. The beam is removed with a sample of E. coli bacterium attached to it. The frequency of vibration is measured and compared to the frequency before it was exposed to the E. coli. How many individual cells of E. coli bacterium are on the beam? Given: wo,before = 1.091 MHz wo,after = 1.070 MHz 5 E. coli cells mE. coli cell = 665 x 10-15 grams mbeam = 365 x 10-10 grams Imaging Devices • Atomic Force Microscopy (AFM) • Scanning Tunneling Microscopy (STM) Imaging Devices • AFM and STM are used for better resolution of nano-particles. •Analysis includes bacteria and protein structure, force measurements within particles, and virus-host interactions. Imaging Devices West-Nile Study •AFM has become the main source of imaging for analysis of virus-host interactions. •A study involving the West-Nile virus gave a more detailed view of the stages the virus goes through during infection. •The images produced reveal changes in plasma and viral budding; this is essential for tracking down the virus’ replication methods. http://www.jnanobiotechnology.com/content/2/1/6 Problem An STM is used to analyze a virus sample. A 350mV potential is applied across the tungsten tip (work function of 4.8eV) and the surface of the sample. If the tunneling probability is 10-8, what is the tunneling current that results? As the tip is moved across the surface the current increases by 50mA. What is the resulting tip-to-sample separation, and what effect does this have on the tunneling probability? Given: T=10-8; V=350mV; Φ=4.8eV; m=9.1*10-31 kg • Solve for electric field, E • From there obtain tip-to-sample separation, d • Tunneling current involves a decay constant, k. determine this constant from virus mass and work function, Φ. • Now solve for current. • Make sure units are correct so that they cancel out properly. Questions???