Magnetic nanoparticle preparation. I made the presentation soon after the Super Saturday 6 week program at Birck Nanocenter where I learned the technology

1. Aqueous Ferrofluid 10.19.2006 By: Victor Samuel 8th Grader at Creekside Middle School Carmel, IN 46032 2006 (Fall session): Gifted Education Resource Institute Super Saturday Program on Nanotechnology

2. Please note that the ferrofluid is difficult to get off clothes. Overview A ferrofluid is a specific type of liquid which responds to a magnetic field. Ferrofluids are composed of nanoscale magnetic particles suspended in a carrier fluid. The solid particles are generally stabilized with an attached surfactant layer. Ferrofluids are extremely stable meaning that they will not cluster together even in extremely strong magnetic fields.

3. Please note that the ferrofluid is difficult to get off clothes. Physics Ferromagnetism is a magnetic dipole that is from the alignment of unpaired electron spins in elements such as iron, cobalt, and nickel. In this experiment we will synthesize magnetic nanoparticles from iron chlorides and then disperse into a tetramethylammoniumhydroxide surfactant to form a colloidal suspension.

4. Please note that the ferrofluid is difficult to get off clothes. Chemistry The formation of ferrofluid involves various types of forces that hold the components together. For example, magnetite is held together by ionic interactions. Ionic attractions between hydroxide anions and tetramethylammoniumcations allow colloidal suspension of the magnetite in the solution. Without the tetramethylammonium hydroxide as a surfactant, the magnetite nanoparticles tend to cluster together. Therefore it is necessary to have the appropriate surfactant to stabilize an aqueous ferrofluid.

5. Please note that the ferrofluid is difficult to get off clothes. Supplies for the Experiment Safety glasses 250 ml plastic bottle 125 ml plastic bottle 2 L plastic jug 100 ml graduated cylinder

6. Please note that the ferrofluid is difficult to get off clothes. Supplies for the Experiment 10 ml graduated cylinder 150 ml plastic beakers Large weigh boats Magnet (reasonably powerful) Stainless steel Scoopula spatula Gloves Cont.

7. Please note that the ferrofluid is difficult to get off clothes. Supplies for the Experiment 500g fecl3~6h2o (ferric chloride) 200g fecl2~4h2o (ferrous chloride) 500 ml ammonium hydroxide (29%) 220 ml Tetramethylammonium hydroxide 500g citric acid Ph paper Distilled water Cont.

8. Please note that the ferrofluid is difficult to get off clothes. Procedure Mix the both the ferric chloride and the ferrous chloride together. While swirling the iron solution with a glass rod, add the ammonia. (1 drop per second) This should make the iron solution turn a blackish color. After all of the ammoium hydroxide has been added stop swirling the solution. Place one of the magnets either on the side or underneath the beaker, this should attract all the nanoparticles to that side of the beaker.

9. Please note that the ferrofluid is difficult to get off clothes. Procedure Keeping the magnet on the side of or under the beaker decant the water. (This means that you should pour off the excess water from the solution) Add a small amount of water to the nanoparticles. Then transfer as much as you can to a weigh boat. Next, decant the water from the weigh boat just like you decanted it from the solution. Then rinse the magnetite off two more times by adding a small amount of water to the solution like you did before. Cont.

10. Please note that the ferrofluid is difficult to get off clothes. Procedure Remove as much water as necessary to form a viscous fluid, but do NOT remove all of the liquid because then you will have made a solid. Add the tetramethylammonium hydroxide solution and mix the ferrofluid by moving the magnet underneath it for two minutes Once mixed (very thoroughly) place the magnet under the weigh boat and remove the excess black liquid. Cont.

11. Please note that the ferrofluid is difficult to get off clothes. Procedure Cont. Place the magnet underneath the weigh boat and keep moving it until you see spiking as shown below.

12. Please note that the ferrofluid is difficult to get off clothes Mechanical Applications Ferrofluids are used in many ways mechanically. They are used in applications such as gas lasers, motors, and blowers. In some of these applications the ferrofluid is held in place by a strong magnet and separate by two different pressured chambers. They are also used as substances for vibrational dampening in electronic applications

13. Please note that the ferrofluid is difficult to get off clothes. Medical Applications Interestingly, ferrofluids could hypothetically be used medically. In one example, if a drug were to be made that cures cancer, we could create a magnetic field around the tumor and that would be used to focus the drug onto the tumor. A ferrofluid could be easily heated locally to burn a tumor. These methods have already been successful in mice studies.

14. Summary Described the background on Ferrofluid including its physical and chemical properties Presented the steps involved in the synthesis of ferrofluid based on my experiment at Purdue during the super Saturday program Highlighted potential application of Ferrofluid Please note that the ferrofluid is difficult to get off clothes.

15. Please note that the ferrofluid is difficult to get off clothes. Acknowledgements Dr. Anne Bentley of Purdue University for helping me with this project. Dave Sedenburg of Purdue University for helping me learn nanotechnology better as a whole. Mr. Anil Gupta, Carmel, IN for giving me the opportunity to join the Fullerene Ministers Robotix Group at Carmel. The Super Saturday organizers at Purdue University for allowing me to have this great opportunity.