Engineering a Scanning Probe Microscope (An Eye for An Eye)
Lesson 9 of 12
Objective: Students will be able to apply practical knowledge of nanotechnology and scanning probe microscopes to the design of their own scanning probe microscope.
This lesson explores how these microscopes gauge the surface of materials at the nano level. Students work in teams to learn about Scanning Probe Microscopes (SPMs) by utilizing a pencil to visually feel the shape of objects they cannot see. Based on the sense of touch through the pencil, students mimic the function of the SPM. They draw what their mind "saw" and compare their results with other student teams, reflect on the experience, and share observations with the class.
1. be able to apply practical knowledge of nanotechnology and scanning probe microscopes to the design of their own scanning probe microscope
2. explain how engineering can help solve society's challenges
Next Generation Science Standards (NGSS)
- Students will develop an understanding of the core concepts of technology.
- Students will develop an understanding of the relationships among technologies and the connections between technology and other fields of study.
NATIONAL BIOTECHNOLOGY STANDARDS
BT. 2.3 Identify past and current discoveries and developments in fields such as, agriculture, diagnostics, medical devices, pharmaceuticals, and research and development.
INQUIRY: How “big” is really, really “small”?
To introduce the lesson, consider asking the students:
"How engineers can measure the surface of things that are too small to see?"
Explore (Guided/Student-Centered Activity)
If internet access is available, have students view the virtual tutorial on Scanning Probe Microscopes and record notes as a part of their background research on this truly remarkable biotechnology. The tutorial will illustrate how scanning probe microscopes work and help students understand how they will perform a similar task through this modeling activity.
Explain (Formulate Ideas)
Class Materials - Box (a traditional shoebox works best) with various items affixed to bottom (suggested items: ruler, paper cup, brick, fruit), blindfold.
Student Team Materials - prepared team "box" to be "scanned", paper, pen, pencil; access to the internet is optional though helpful, metric ruler, string, other measuring devices
1. Each student takes turns using a pencil probe to determine the shape or identify of an object in a box. They may either be blindfolded, or have a hole cut into a box so that their hand and the pencil can be inside without seeing what is in the box.
2. Use just the tip of the pencil to examine the content or surface area of the bottom of the box. Student design methods for keeping track of the height of the objects they sense, their shape, and overall size and record their quantitative or qualitative measurements.
3. Next, students will draw what they "saw" on a piece of paper -- they might want to consider a top and side view to help determine what is in the box.
4. When each student on the team has done the investigation, work together and share your drawings and opinions of what is in the box. Come up with a consensus as a team and develop a final drawing that includes estimated measurements of the object.
5. Each student team presents their ideas, drawings, and measurements to the class, and listen to the presentations of the other teams. Team should compare the result of their “probe” to other teams to see how close they were or the other teams were, in determining the actual size and shape.
Elaborate (Apply and Extend Understanding)
Show students photos which were taken with Scanning Probe Microscopes. Have students guess what the image is in full scale and record their predictions on a notetaker like the one provided! A Google Search for "scanning electron microscope photos" will yield a great deal of photos that can be used in this portion of the lesson.
ASK: How useful is this new technology?
(Target response: Scientists and engineers are now able to manipulate of atoms and molecules individually and with a great degree of precision. They can create new ways to perform things like surgery or new ways to treat the root cause of disease which is mainly at the subcellular level.)
ASK: Where do you envision this technology being a game-changer?
(Target response: Nanotechnology shows the most promise in it's biomedical and bioengineering applications such as diagnostic techniques, drug and implants. Machines and tools that are built on the nano scale can be used to remove obstructions in the circulatory system and to kill cancer cells.)
Evaluate (Monitor Understanding)
As we close this lesson students are given the opportunity to connect the introduction of this novel technology to the future successful of the biotechnology industry. The reflection portion of the lesson can be completed as an Exit Ticket, Stop and Jot, or Quikwrite however reflections can also be conducted as small group discussions and Socratic Seminars. Students should respond to the following:
Reflection: What critiques, suggestions, or recommendations can be made that would enable improvements to your groups designs? Based on this novel technology, what is the next great advancement in biotechnology technology? Did you think that working as a team made this project easier or harder? Why?