Nanoparticle Diffusion in Biofilms

Biofilms are thin, gooey films of bacteria that stick to surfaces and consist of cells and extracellular polymeric substance (EPS). Biofilms are up to one thousand times more resistant to antibiotics than planktonic bacteria, making their resistance a critical consideration in medical implants and devices. We hypothesize that dense EPS networks increase biofilm resistance to infiltrating substances. In our study, quantum dots, a type of nanoparticle with stable fluorescence, are tracked in biofilms and control glycerol-water solutions to determine their diffusion properties. We developed single particle tracking techniques at lower magnifications and at higher frame rates than previous publications. Using this technique, we replicated the results of prior research in control glycerol-water solutions. Our goal is to provide quantitative biofilm infiltration metrics for further optimization of novel infection therapeutics.