The discovery of antibiotics in the early 20th century changed modern medicine. Simple infections like a paper cut used to kill people became easy to treat. Deadly diseases like tuberculosis and smallpox become curable. The average life expectancy at birth jumped from 47 years to 78 years. However, the overuse and misuse of antibiotics in humans and farm animals have led to the rapid increase of antibiotic-resistance bacteria. For example, the U.S. sold about $600 million dollars of antibiotics ointments every year. The overuse of triple-antibiotics first-aid ointment may create a skin infection superbug called USA300. We need to reduce the use of antibiotics unless it is absolutely necessary. According to a UK study, by 2050, 10 million people will die from antibiotic-resistant infections. That is more than the number of deaths caused by cancer and diabetes combined.
I invented a first aid liquid bandage that doesn’t contain any antibiotics in it. My research is to see if nano-copper and nano-silver can be used as antibacterial agents in first aid ointment to reduce the need for antibiotics. Copper and silver have been used for health purposes since ancient times. Egyptian and Babylonian soldiers would sharpen their bronze swords after a battle, and place the filings in their wounds to reduce infection and speed healing. Silver has been used extensively throughout recorded history for a variety of medical purposes. I have experimented with nano copper and nanosilver. I found out that nanosilver was more effective at killing bacteria so I decided to continue my studies with nanosilver. I used an environmental-friendly method, called biosynthesis, to make the nanosilver. I used lemon leaves and distill water to make a lemon leaf solution, which acts as the reducing and capping agent. I then mixed it with silver nitrate to finish off my biosynthesis. I characterized the nanoparticles under a Transmission Electron Microscope at the University of California, San Diego, and determined that the particles were spherical shaped and were around 5 to 30nm. Next, I mixed the nanosilver with a water-soluble polymer called PVP to create the liquid bandage. The PVP can protect the wound by forming a thin film of the polymer when the liquid evaporates. I tested the effectiveness of my liquid bandage by using the Kirby Bauer zone inhibition method with 3M Petri films and Petri plates. Four types of bacteria were used in the experiments - Bacillus Subtilis, E. Coli, Micrococcus Luteus, and soil. Five different concentrations of the nanoparticles solution were used to kill each type of bacteria. The concentrations were 500 ppm, 250 ppm, 125 ppm, 62.5, and 31.5 ppm. For the nanosilver solutions, the concentrations that were used were 100 ppm and 30 ppm. I used Neosporin as control.
The test results showed the nanosilver liquid bandage can inhibit the growth of soil bacteria, Bacillus Subtilis, and Micrococcus Luteus. The higher the concentration, the better the bacteria inhibition. The minimum inhibition concentration (MIC) is 63ppm. The nanosilver liquid bandage is easy to use, inexpensive, and nontoxic to the skin. Additionally, it can help mitigate the overuse of antibiotics and hopefully save millions of lives.