Cleaning of titanium substrates after application in a bioreactor

Area of Science:

• Biomaterials Science
• Surface Chemistry
• Microbiology

Background:

• Titanium is a potential substrate for biofilm reactors.
• Biofilm formation on titanium surfaces presents cleaning challenges.
• Standard solvent cleaning may be insufficient for complete biofilm removal.

Purpose of the Study:

• To evaluate the efficacy of oxygen plasma sputtering for cleaning titanium surfaces contaminated with biofilms.
• To assess the suitability of microstructured titanium as a biofilm reactor substrate.
• To compare oxygen plasma cleaning with standard solvent-based cleaning methods.

Main Methods:

• Biofilms of Pseudomonas fluorescens and Paracoccus seriniphilus were grown on plain and microstructured cp-titanium samples in a flow cell.
• Samples were cleaned using a standard solvent-based procedure (acetone, isopropanol, ultrapure water) followed by oxygen plasma sputtering.
• Surface analysis was performed using X-ray photoelectron spectroscopy, fluorescence microscopy, confocal laser scanning microscopy, and scanning electron microscopy.

Main Results:

• Oxygen plasma sputtering effectively removed all biofilm components, fully restoring titanium surfaces.
• Solvent-based cleaning alone did not reliably remove the biofilm.
• Microstructured surfaces supported biofilm growth but were fully restorable by plasma treatment without structural damage.

Conclusions:

• Oxygen plasma sputtering is a necessary and reliable method for complete biofilm removal and surface regeneration on titanium.
• Microstructured titanium is a viable substrate for biofilm reactors, offering enhanced biofilm growth while maintaining cleanability.
• The cleaning procedure is critical for reliable biofilm removal and surface restoration in biomaterial applications.