1. CHEMISTRY & PHYSICS OF THE BIOSENSOR More of the Capture Membrane!

2. Polyaniline and CNT’s are used in the Capture Membrane

3. POLYANILINE: an important nanotech plastic A conducting, organic plastic often used with CNT’s Can tell whether an acid or base is in the air Sensitivity to an acid or base increases with surface area Surface area is determined in the creation of the polyaniline by creating more bumps and valleys that are nano size. The Conductivity changes due to exposure to acid (vinegar) or a base (ammonia).

4. POLYANILINE: a material of promise! The amount of required conductivity is designed into the pani (polyaniline) It can be melted into a liquid easily Or it can be put into solution (like sugar & water) It’s easy to make required shapes with pani No environmental problems with disposal

5. PANI – applications since 2000 Electronics –Super-capacitors –Super-magnets –Integrated circuits –Luminescent diodes –Sensors Chemical Power sources Conductive fabrics Anti static coatings

6. PANI/CNT SENSORS POLYANILINE attached to CNT can become excellent sensors of bacteria & viruses! Why would we want to develop this????

7. Earlier you found out what Temperatures and PH’s PANI was more conductive at. What were your results?? Do you remember??

8. The Biosensor & it’s basic parts

9. PHYSICS STUDENTS What do you think the circuit looks like? Is it a parallel or series circuit? What could be used that is small enough for a voltage source? When the antigen is found – how will that close the switch to send the electronic signal? How will we want to know that the signal has been sent? What’s practical here?

10. The Capture Membrane & the Circuit Diagram

11. Assignment A: You will be building a large scale biosensor circuit. You will want to capture something large (such as a magnet or a toy car) as it travels past your circuit. This will be your switch. Use a voltage source of a battery of appropriate size. When your switch is closed (on) have it light up a light bulb or turn on a buzzer. Design into your circuit appropriate places for a Ammeter.

12. Parameters of the Project (teams of 2) Draw a circuit diagram and have your teacher approve it. Make a list of supplies needed & have your teacher approve it. Make a list of tests you should run once it’s working & have your teacher approve it. Build it! Ask your teacher for help if you are having trouble getting it to work. Run your tests! Analyze your data & write a conclusion!