Gold Nanoparticle SynthesisPlace a 50 mL round bottom flask on a weighing scale and make sure it is set

to measure in milligrams. Add 7.88 mg of Gold (III) Chloride to the flask, then add 20 mL of distilled water to the flask. Drop a magnetic stirring bar into the flask and swirl the flask until the solution is mixed thoroughly. Connect the flask to a ring stand and half-way submerge it into mineral oil on top of a hot plate. Set the hot plate to 900 RPM and to 115 degrees Celsius. While this heats up, make a one percent solution of sodium citrate and dihydrogen monoxide by measuring 12.5 mg of sodium citrate on weighing paper and placing it into a five milliliter volumetric flask, then adding 1.25 mL of distilled water. When the chloroauric acid solution reaches the desired temperature, add the sodium citrate solution rapidly. A slow color change should result, turning the yellow-colored solution into a deep red wine color. This color change marks the end of the gold nanoparticle synthesis reaction, and the final solution can be transferred into a desired container.

Silver Nanoparticle Synthesis Create an ice bath by using a round-bottom bowl from a hot plate. Add

enough ice from the stock room to nearly fill the bowl. Place a 50 mL round bottom flask on a weighing scale and make sure it is set to measure in milligrams. Add 2.27 mg of sodium borohydride to the flask, and then add 30 mL of distilled water. Place a stirring bar in the flask. Halfway submerge the flask in the previously-made ice bath (a ring stand may also be used). Leave the solution in the ice bath for 20 minutes. During this time, make the 0.2 M silver nitrate solution by adding 1.7 mg of silver nitrate to 5 mL of distilled water. After 20 minutes have passed, add 4 mL of the silver nitrate solution just made into the sodium borohydride solution in the ice bath at a rate of approximately one drop per second. A relatively rapid color change should result so that the solution changes from clear to deep yellow. Once this is observed, remove the solution from the ice bath and add a couple drops of 0.3% PVP solution to the flask to better purify the solution. This marks the end of the silver nanoparticle synthesis and the final solution can be transferred into a desired container.

Materials:50 mL round bottom flaskmagnetic stirring barweighing scale (mg)weighing paper Gold (III) ChlorideDistilled waterMineral oilHot plate Ring standSodim citrateIceRound-bottom bowlSodium borohydride

Silver nitrate PVP