Bactericidal Effect of Silver Nanoparticles - Lab Report Example

Incubate at 37C in a shaker incubator for an overnight culture so that the bacteria would be in log phage. After that spin cultures at 6000 PRM for 10 minutes. Remove supernatant, leaving 5 ml in each tube. Resuspend pellet in the remaining supernatant and add 1ml of sterile nutrient broth to the disposable plastic cuvette and blank spectrophotometer. Add 1ml E.coli culture to plastic cuvette and record A600 (make sure A600 ˃ 0.5). For each Ag+ compound (WI, WII, WIII, WIV, and WV) and +Ve control, take 10 ml dilution.

Prepare 17 autoclaves from liquid culture tubes from the nutrient broth. The final volume is 10 ml.Dilate each concentration on Ag+ until 1ppmAdd 50 ml of E. coli for each different compound of Ag+ silver ions. In the same way, add 50 ml of S. aureus for each different compound of Ag+ silver ions. For each compound of silver ion, one needs to incubate at 370 C in zero time, 4 times and 24 times to try to get a Time serious at the effective concentration to take samples at 0 hours, 4 hours and 24 hours to try to get a Time: Concentration for Lethal does.

At zero time for small tubes for each compound of silver ions and control, make dilution at 1:1, 1:102, 1:103 Spread plate. 50 μl of circled dilutions above on nutrient agar plates. Spread 50 μl of – ve control (no bug) controls. Incubate overnight culture at 37 C.Count colonies.To obtain CFU/ml= CFU20dilution factor.At 4 times for small tubes of each compound of silver ions and control, prepare before taking the sample from them and make dilution at 1:1, 1:102, 1:103. Spread plate.

50 μl of circled dilutions above on nutrient agar plates. Spread 50 μl of – ve control (no bug) controls. Incubate overnight culture at 37 C.Count colonies.To obtain CFU/ml= CFU20dilution factor.At 24 time for small tubes of each compound of silver ions and control what I prepared before taking the sample from them and make dilution at 102, 1:103, 1:104, 1:105, 1:106. Spread plate. 50 μl of circled dilutions above on nutrient agar plates. Spread 50 μl of – ve control (no bug) controls.

Incubate overnight culture at 37 C.Count colonies.To obtain CFU/ml= CFU20dilution factor.ReferencesHumberto H. Lara, 2009, “Bactericidal effect of silver nanoparticles against multidrug-resistant bacteria”Retrieved November 12, 2009, fromhttp://www.springerlink.com/content/g32341574x6q1k51/