Preparation of antibacterial coating against S. aureus

Objectives: Objectives. Proliferation of bacteria on various medical devices may cause infection in patients. Surfaces antibacterial features may reduce the risk of microbial contamination. This could be achieved by surface coating with an antibacterial layer. Non-leachable, long-term protection against pathogens such as Staphylococcus aureus is desirable. In this study, new antibacterial coating material was prepared using t-Cinnamaldehyde (t-CIAL), naturally existing bactericide, and silane coupling agent.
Methods: Methods. Two samples of modified coupling agents were prepared by reacting t-CIAL and 3-aminopropyltriethoxysilane (APTS). Both reagents were reacted at 1:1 equivalent under acid catalysis, producing imine molecule (A) via reductive ammination reaction. 2 equivalent t-CIAL were used while continuous reduction with NaBH₄ producing tertiary amine (B). Mass and infrared (IR) spectrometry was used for structure evaluation. Antibacterial effect against S.aureus was tested following direct contact with coated glass slides with A and B. Tested surfaces were imprinted onto blood agar. Colonies density was examined.
Results: Results. Mass spectrometry for A and B were 336.22 and 454.31 respectively, confirming molecules’ structure. A and B IR spectrometry showed absence peaks at 1720cm^-1 and at 3500cm^-1 for aldehyde and primary amines, which was found only in the raw materials. Bacterial growth was observed only on samples A and on the control group, but not on the samples B.
Conclusions: Conclusion. Newly synthesized coupling agent based on alcoxysilane conjugated with cinnamaldehyde is a possible coating to prevent surfaces S. aureus infections.