Project Summary/Abstract Bacteria in biofilms are more responsible than planktonic cells, for food contamination, infection during cleaning, and are responsible for 80% of all hospital acquired infections, about 1.6 million infections and 80,000 deaths, at an annual cost of $16.8 to $27.2 billion dollars in the US. Treating biofilms on surfaces requires constant cleaning as, for example, biofilms that are able to rejuvenate within 30 minutes after raw milk is introduced to a milk evaporator. Biofilm infections on implanted medical devices make up half of the hospital acquired infections and the primary treat is to remove the device, increasing surgery and increasing risk of secondary infection. Biofilm development and reaction to antibiotics are dependent on the geometry, nutrient, and liquid flow conditions and there are currently few relationships available to translate between one set of conditions and another. This program seeks to create platforms and mathematical relations that will increase the ability of researchers, clinicians and manufacturers, to translate from fundamental studies on biofilms with finite time scales and materials to infections and surfaces. The primary platforms that the proposal seeks to explore are those that can monitor the impact of external stress, like temperature, fluid shear, antibiotics, nanoparticles at each stage of biofilm development and simulate real world conditions. Some of those platforms initially proposed are those that can be made using 3D printers and those that can be easily scaled, like rotating disk systems. The primary mathematical relations that will be proposed are dimensionless numbers that can be used to translate from one experimental apparatus to another. Four dimensionless numbers have been proposed for biofilms and three have been proposed for communication in biofilms, though their use is spare. Part of this proposal seeks to determine what role, if any, sociomicrobiological interactions, play in biofilm persistence. For example, Candida albicans increases meropenem tolerance of Pseudomonas aeruginosa. The use of waste byproducts as a means of interaction will likely be prioritized, like how sugar consumed by Candida may be responsible for the increased tolerance mentioned previously. Finally, this proposal also seeks to determine how biofilm substitutes can be used to study the impacts of external stress, like how fluid shear stress and temperature affect antibiotic and nanoparticle and uptake. While neither clinical nor animal trials are proposed in this study, a participatory dialogue will be conducted between the researchers, clinicians, manufacturers, and engineers, and sanitation and hygiene professionals to ensure that results from this research can be used.