The Effect of Silver Nanoparticles on the Growth of Escherichia coli

This experiment verified that silvers antibacterial properties slow and yield the growth of bacteria. To test this, a bacteria solution of E. coli and water was placed on two groups of 30 samples; these two groups being silver nanoparticle cloth pieces and cotton cloth pieces. The cloths were incubated for 24 hours before each sample was placed in a 9mm test tube. Once in the test tubes, nutrient broth was placed into the test tubes and an initial reading from the light spectrometer was recorded. The 60 total test tubes were placed back into the incubator for another 24 hour period. A reading of the samples was recorded after the incubation period. The results were analyzed with a two sample t test. The t test produced a t-value of -10.3923 that yielded a p-value of 9.61E-13. The null hypothesis was rejected. There is significant evidence that the growth of Escherichia coli on the cotton cloth was greater than the amount of Escherichia coli that that was able to grow on the cloth with silver. The p-value of 9.61E-13 is smaller than the alpha level of 0.05. There is 0% chance of getting these results by chance alone if the null hypothesis is true. This means that the presence of silver nanoparticles inhibited the growth of E. coli.

Research Conducted By:

Matthew Cherry
Cousino High School

Cooper Homic
Cousino High School