1. Gather all materials.
2. Put on a pair of disposable gloves.
3. Make a paper towel damp with some 70% isopropyl rubbing alcohol. Wipe down the work surface with the rubbing alcohol-dampened paper towel.
4. Using a permanent marker, label the five baby food jars #1 to #5.
5. Using the 25 milliliter (mL) graduated cylinder, measure and pour 22.5 mL of distilled water (from a new, unopened container) into each of jars #2, #3, #4, and #5.
6. Using the 25 mL graduated cylinder, measure and pour 25 mL of the colloidal silver solution from the original bottle into jar #1. Jar #1 will hold the 500,000 µg/L (undiluted) concentration of colloidal silver.
7. Transfer 2.5 mL of the undiluted solution from …show more content…
Transfer 2.5 mL of the 5,000 µg/L solution from jar #3 to jar #4.Taking the solution from jar #3 (instead of jar #1) and put it into jar #4 (instead of jar #2).Jar #4 now holds the 500 µg/L concentration of colloidal silver.
12. Transfer 2.5 mL of the 500 µg/L solution from jar #4 to jar #5.Taking the solution from jar #4 (instead of jar #1) and put it into jar #5 (instead of jar #2). Jar #5 now holds the 50 µg/L concentration of colloidal silver.
Testing the Antimicrobial Activity of the Silver Nanoparticles
1. Punch 15 circles from a filter paper with the hole punch.
2. Using clean tweezers, place three filter paper circles) into each baby food jar (#1 through #5). Let them soak until you need them in step 10
3. Lay out five of the nutrient-agar prepared media plates. Place the plates upside down on the clean counter or table and use the permanent marker to label the back of each one, #1 through #5.
4. After labeling them, flip the plates over so that the lid is on top.
5. Take off your gloves and put on a new pair of disposable gloves.
6. Sterilize the tweezers by dipping them into 70% isopropyl rubbing alcohol for about 10 seconds. Then remove the tweezers from the alcohol and wave them in the air for about 20 seconds.
7. Using the tweezers, grab a cotton swab from a new, unopened box of cotton