REDUCING ANTIBIOTIC RESISTANCE AND MIC USING SILVER NANOPARTICLES WITH ANTIBIOTICS

As antibiotic resistance becomes a larger issue due to overuse and misuse, silver nanoparticles are being studied as potential antimicrobial agents. The researcher questioned, if inorganic silver nanoparticles (AgNP) are applied in combination with an antibiotic, compared to the antibiotic alone, will bacteria such as Escherichia coli (E. coli) or Enterococcus faecalis (E. faecalis) develop resistance less easily? This investigation tests the use of silver nanoparticles in combination with an antibiotic to reduce antibiotic resistance and minimum inhibitory concentration (MIC) required to inhibit bacterial growth. The first hypothesis, that if a resistant strain of E. coli is tested against AgNP, then AgNP will inhibit growth, is proven correct. The data shows that 1mL of AgNP inhibits growth of ampicillin resistant E. coli in 4 mL of broth. The second hypothesis is that, if AgNP are applied in combination with an antibiotic, then MIC is reduced. The second hypothesis is proven correct and the data shows that the combination of streptomycin and AgNP inhibits E. coli growth for more than 72 hours, longer than for streptomycin or AgNP alone. MIC is also reduced with the combination of streptomycin and AgNP together inhibiting more growth than antibiotic or AgNP alone. The synergistic combinations of streptomycin with AgNP and ampicillin with AgNP are significant because MIC is reduced when a smaller concentration of antibiotic is required to inhibit bacterial growth. A reduction in the use of antibiotics, when combined with AgNP, can minimize the incidence of antibiotic resistance while maintaining minimum inhibition concentration.