Discovering Nanotechnology

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2 Glossary Agarose Nanotechnology A polysaccharide derived from seaweed that is used for the separation of molecules in electrophoresis. A term used to describe the production and the uses of nanoparticles in many scientific fields including engineering, medicine, electronics, food and many other industries. Objectives of the workshop Understand the structure of nanoparticles and their place among the different sizes of everyday materials. Learn how to prepare nanoparticles from preferred chemicals. Learn the historical to modern use of nanoparticles in technology, medicine and other fields. Learn the future prospects of Nanotechnology and how this field of science can change the future. Equipment list Activity 1: Virus identification using immunoassays (may be excluded if time is restricted) Agarose gel plates (small petri dishes) Human blood (fake) sample A Serum samples (fake) B, C, D & E Straw to make wells Instruction sheet Waste bin Activity 2: Conceptualising Nanoscale Six (6) images of micro and nanoscale specimens Activity 3: Detecting concentrations Five (5) falcon tubes (50ml) from 1 to 5 Number 1 tube with 50ml of concentrated orange (powdered) suspension. Tube stand Beaker full of tap water Instruction sheet Activity 4: Seeing the Unseen A locked activity box with a DUPLO structure pre fixed inside A skewer with markings for distance measurements Building blocks for the activity Instruction sheet

3 Safety notes for students Students should not touch the agarose gels with their hands and must be washed if touched accidently. Shouldn t should not spill or touch serum (fake) samples No food or drinks are allowed in the lab and the orange mix must not be consumed Students should wash their hands before leaving workshop Safety notes for QUT ambassadors Heatproof gloves to be used when handling heated agarose gel Background Although nanotechnology is a fairly new science, the chief concepts have been developing over the course of fifty years. Interestingly, we have been employing nanotechnology for over a thousand years; from painting to making steel. Although, what has changed recently is our ability to manipulate and engineer in the nanometer scale. Nanoparticles are so small they contain just a few atoms to a few thousand atoms, as opposed to bulk materials that might contain many billions of atoms. This difference is what causes nano materials to behave differently than their bulk counterparts. The word itself is a combination of nano, from the Greek nanos (or Latin nanus ), meaning Dwarf, and the word "Science." Nano refers to the 10-9 power, or one billionth. In these terms it refers to a meter, or a nanometer, which is on the scale of atomic diameters. For comparison, a human hair is about 100,000 nanometers thick. Nanoscience is the study of atoms, molecules, and objects whose size is on the nanometer scale (1-100 nanometers). Physics is different on the nanometer scale. Properties not seen on a macroscopic scale now become important- such as quantum mechanical and thermodynamic properties. Rather than working with bulk materials, one works with individual atoms and molecules. By learning about an individual molecule s properties, we can put them together in very welldefined ways to produce new materials with new and amazing characteristics. There are multiple reasons for this. One is availability of new instruments able to see and "touch" at this scale. In the early 1980 s the scanning tunneling microscope was invented at IBM-Zurich in Switzerland. This was the first instrument that was able to see atoms. A few years later, the Atomic Force Microscope was invented, expanding the capabilities and types of materials that could be investigated. Hence, Scanning Probe Microscopy was born, and since then multiple similar techniques have evolved from these instruments to see different properties at the nanometer scale. In addition, older techniques such as electron microscopy have continued to evolve as well, and now can image in the nanometer range.

4 Currently, there are a large number of complementary instruments that help scientists in the nano realm. In addition to the enabling technologies, scientists have realized the future potential of this research. By convincing politicians and leaders around the world, countries have instituted initiatives to promote nanoscience and nanotechnology in their universities and labs. With the recent increase in funding, many scientists are pursuing this research and the rate of discovery has increased dramatically. Source: Workshop activities In this workshop there are three hands-on activities Virus identification using immunoassays, detecting concentrations and seeing the unseen. The class is split into 4-6 groups and each group will have one set immunoassays to use. The fourth activity is not hands-on, and consists of some images to be arranged in their order of physical size. Activities are run as follows: Activity 1: Virus identification using immunoassays Presenter will set 6 agarose gel plates and serum samples with the instruction sheets. 1. Make five (5) wells on the agarose plate as shown in the instruction sheet using the straw. 2. Dispense the gel plugs in to the waste container. 3. Place the plate on the figure in the instruction sheet and DO NOT move it or rotate it. 4. Put 1-2 drops of Human blood sample (A) into the centre well. 5. Put 1-2 drops of each serum sample (B, C, D and E) in to the corresponding wells. 6. Close the plate and allow the test to react for 15min. complete other activities and take the results at the end of all. Activity 2: Conceptualising Nanoscale Presenter will place 6 electron micrographs in a random order with the instruction sheet. 1. The students must re-arrange the images according to their actual sizes considering the information given on each image and their analytical skills. Activity 3: Detecting concentrations Each set will be given 5 falcon tubes with No. 1 containing 50ml of concentrated orange powder suspension. 1. Transfer 10ml from tube 1 to tube 2 and top the tube 2 to 50ml with tap water. 2. Transfer 10ml from tube 2 to tube 3 and top the tube 3 to 50ml with tap water.

5 Immunoassay 3. Follow the same procedure up to tube Observe the colour and odour change from tube 1 to 5. Discovering Nanotechnology Activity 4: Seeing the unseen 1. Push the probe through the hole located at grid point A1. 2. Use the markings on the probe to measure the depth that the probe reaches. Record your measurement in the table on your worksheet. 3. Continue taking measurements from all of the holes on the grid. 4. Now use the blocks to try and build a model of the surface in the box. 5. When you are finished making your model, check inside the box to see if you got it right. Rundown of workshop Time Activities 0-20 Presentation get students into groups All the groups will complete the activity 1 and leave for reaction Students will complete the activities 2, 3 and Students will observe the immunoassay results. Go through results and answer questions. A good example of a set up is shown on the following page. The sets are best spread out as much as possible around the room. Groups can work on opposite sides of protruding bench if possible to share the Immunoassay waste bins. The laminated images kept on the desks. Seeing the Unseen (3 sets) Conceptualising Nanoscale (3 sets) Detecting concentrations (3 sets) Presenter

6 Script A PowerPoint presentation is used for this activity. This acts as the main script for the workshop (see notes section at bottom of each slide). Hi, my name is.. and I am from QUT Extreme Science and Engineering. Today we are going to learn about the nanotechnology and how nanotechnology can be used. Can anyone tell me what nanotechnology is?... With this introduction follow each slide and explain the information on each slide to the class and show them the examples of nanoparticles and innovations such as the ferrofluid (to be passed around) and fabric with nano whiskers and nano-treated glass (demonstrated using water dropped on samples from pipettes). If time and expertise permits, demonstrate the production of gold nano particles using the gold chloride solution at the end of the presentation. If time allows, show this Youtube clip: It shows recent research and developments in the area of superhydrophobic materials that are now being sold in the US. Instructions for making agarose A ~1% (w/v) agarose is used for making gel plates. Preparation is as follows: 1. Measure the appropriate amount of agarose using the measuring spoons and put it into the 500mL Schott bottle. 2. Measure the corresponding amount of tap water and add in to the bottle. 3. Swirl the agarose and water to mix. 4. Loosen the lid a little and microwave the mixture until all the agarose is dissolved, and the solution is clear and homogenous (2-4 mins depending on volume). Don t allow the solution to boil too much. 5. Open the lid of the jar and allow the molten agarose solution to cool down (5-10 mins). 6. Pour the agarose into the bottom plate of the petri dish and allow to solidify. Worksheet On the following page is the worksheet used for this workshop. Acknowledgments This document was compiled by Chaminda Ranasinghe and Maria Barrett.

7 Worksheet Discovering Nanotechnology Virus identification using immunoassays 1. For which virus was the person carrying antibodies? 2. Using current methods of virus detection, a vial of blood is needed for one or two tests. What might be an advantage of using this type of detection device? Conceptualising Nanoscale 1. List what you think is the correct order for the images from largest to smallest. 2. If 1000nm = 1µm; 1000µm = 1mm; 1000mm = 1m; how tall are you in nanometres? Detecting concentrations 1. At which concentration was there no colour? 2. At which concentration could you not detect odour? 3. In test tube #5 there is no odour or colour, but are there still orange cordial particles in this test tube? Explain your answer.

8 Seeing the Unseen 1. Complete the table. Next to the co-ordinate, record the depth that the probe reached. A1 A2 A3 A4 B1 B2 B3 B4 C1 C2 C3 C4 2. Using this equipment as a model, what do you think are some of the benefits of using scanning probe microscopes? 3. What might be some of the limitations of using scanning probe microscopes? 4. What could be done to improve this model of a scanning probe microscope?