(330a) Direct Imaging Methods Show Limitations of Traditional Biofilm Staining Techniques

Biofilm research is of great importance to better understand the microorganisms that pose major threats to food safety, security and public health. Biofilms are most frequently characterized using staining techniques in a well plate. The inherent drawbacks of traditional staining assays invite the development of orthogonal techniques to assess biofilm formation. In this work, we present a set of simple and direct imaging methods to detect biofilms at both solid-liquid and air-liquid interfaces in four bacterial species with a diverse range of biofilm forming abilities. By cultivating biofilms at an air-liquid and particle laden air-liquid interface in a well plate and a pendant droplet, these non-traditional imaging methods highlight false positives for biofilm detection using the traditional crystal violet staining assay.