A new transparent coating that causes bacteria to slide off of toilet bowls has been developed by researchers from Erciyes University Nanotechnology in Turkey.

To create the coating, researchers ground poly(dimethylsiloxane) (PDMS), which is a silicone oil, in a ball mill for about 60 minutes. Within the mill, the chemical bonds of the PDMS were broken down via exposure to small tungsten carbide balls at high speeds, thereby leading to the creation of new molecules. The researchers suggested that the milled PDMS would instantly graft onto surfaces like glass or porcelain, subsequently creating a durable and oily coating.

An easy-to-apply polymer coating made the toilet bowl on the left more slippery than the untreated one on the right. Source: ACS Applied Materials & Interfaces (2023). DOI: 10.1021/acsami.3c11352

To test the coating’s effectiveness, the milled oil was applied to one half of a sterilized toilet bowl's interior, while the other half of the toilet bowl’s interior was left untreated. Sterile human urine mixed with E. coli and S. aureus bacteria was then poured into the toilet and both sides of the toilet bowl were eventually swabbed. According to the team’s findings following a series of bacteria culture tests, the PDMS-coated portion of the toilet bowl prevented 99.99% of bacterial growth when measured against the uncoated section.

An article detailing the coating, “Mechanochemical Activation of Silicone for Large-Scale Fabrication of Anti-Biofouling Liquid-like Surfaces,” appears in the journal ACS Applied Materials & Interfaces.