Biofilms are aggregates of organized growth of microorganisms. Bacteria irreversibly attach to the surface of inert or active entities, multiply, differentiate, and secrete some polysaccharide matrix, which is a bacterial aggregate membrane formed by wrapping the bacterial community in it. A single biofilm can be formed by one or more different microorganisms.
- Transmission electron microscope (TEM)
Due to the insufficient stabilization of polysaccharides by conventional fixatives such as aldehydes, glutaraldehyde, paraformaldehyde, and osmium tetroxide, we removed the moisture of the biofilm by fractional dehydration with alcohol after the fixation step thereafter. After the sample is infiltrated with resin, the sample is embedded in gelatin capsules and polymerized. The sections were then post-stained with uranyl acetate and lead citrate. Monitoring of cellular components can be performed directly in TEM by negative staining.
- Scanning electron microscope (SEM)
The procedure for SEM is similar to TEM with the addition of some chemicals, and the post-fixation and dehydration steps for SEM are similar to those for TEM as in the steps of the TEM method. This step is applied after drying in the dehydration step and coating the sample with gold in processing for SEM, rather than resin infiltration, embedding in gelatin capsules, and lead citrate and acetic acid in processing for TEM Uranyl staining. After dehydration with graded alcohol, the samples were dried and coated with gold palladium. After completing all these steps, observe the sample in SEM.
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