Materials List: Thirsty for Gold
Each group needs:
- 20 ml gold colloid (have students synthesize these gold nanoparticles using supplies listed below and instructions in the Procedure section; alternatively: purchase the gold nanoparticles—see suggested source below, or ask for a small supply from your local university)
- Gatorade IceTM (colorless flavor), 2 drops
- pickle juice with little color, 2 drops
- Pedialyte® (flavorless), 2 drops
- PowerAdeTM (any colorless flavor), 2 drops
- 4 1-dram glass vials (at https://www.sks-bottle.com/340c/fin11a.html or https://www.amazon.com/Glass-Vials-Dram-Pack-12/dp/B002JV6976)
- 4 disposable plastic pipets
- glass waste container with screw-top lid
- gloves and goggles for each student
- Thirsty for Gold Worksheet, one per student
Supplies for gold nanoparticle fabrication by teacher for the entire class:
- 20 ml of 1.0 mM HAuCl4, gold (III) chloride hydrate; for example, part #244169-500 mg for $98 at www.sigmaaldrich.com. NOTE: To make 20 ml solution of 1.0 mM HAuCl4, dissolve 7 mg of solid gold (III) chloride hydrate in distilled water.
- 2 ml of 38.8 mM Na3C6H5O7, sodium citrate anhydrous; for example, part #W302600-Sample K for $40 at www.sigmaaldrich.com. NOTE: to make 2 ml of 38.8 mM sodium citrate anhydrous, dissolve 14.86 mg of solid Na3C6H5O7 in 2 ml of distilled water.
- stirring hot plate
- magnetic stir bar
- distilled water, 50 ml (this is water for the above solution preparation and additions as solutions boil)
- (optional) refrigerator, for cooling solution, and fume hood
To purchase gold nanoparticles (or ask for a small supply from your local university biochemistry or chemistry programs):
- Get enough for 20 ml gold colloid per group
- Example source of gold colloid: part #752568 for $298 at www.sigmaaldrich.com. NOTE: It is much less expensive to source raw chemicals and make solutions, and raw materials last for multiple activities.