Healthcare-associated infections (HAIs) pose a significant threat in medical settings, often arising from contaminated surfaces and devices. Despite stringent sterilization protocols, these infections can still occur, leading to severe complications for patients. Researchers are continually seeking innovative solutions to enhance infection control and safeguard patient health. One promising approach involves using special antibacterial coatings that can be applied to medical devices and blood product storage bags, reducing the risk of infection transmission. Recent advances in this field have shown that polydopamine, a bioinspired polymer, holds great potential in preventing HAIs through its antibacterial properties.

Researchers from Héma-Québec and Université Laval have developed an innovative solution to combat these infections using unmodified polydopamine (PDA) coatings. This groundbreaking study, led by Dr. Danny Brouard along with Sahra Fonseca, Nicolas Fontaine, Marie-Pierre Cayer, Jonathan Robidoux, and Professor Denis Boudreau, has been published in the peer-reviewed journal Next Materials.

The primary motivation behind this research was to optimize the antibacterial efficacy of PDA coatings to reduce the risk of transfusion-transmitted bacterial infections. The team explored various conditions for synthesizing PDA, including dopamine monomer concentrations, sample positioning, stirring speeds, and reaction times. These parameters significantly influenced the morphology and wettability of the PDA coatings, which in turn affected their antibacterial properties.

One of the most notable findings of the study is that the PDA coatings demonstrated a reduction in bacterial load, particularly against Staphylococcus aureus. However, the coatings showed less effectiveness against Escherichia coli, highlighting the need for further optimization depending on the bacterial strain and application requirements. 

The researchers used advanced characterization techniques, including UV-visible spectrophotometry, contact angle measurements, and atomic force microscopy, to characterize the coatings. However, excessive roughness did not always correlate with better antibacterial performance, suggesting that other factors, such as surface charge and hydrophobicity, also play a role.

Importantly, the research also confirmed that PDA coatings are non-cytotoxic to human cells, possibly making them safe for medical applications. “The minimal cytotoxicity of polydopamine is a crucial finding, as it ensures the safety of these coatings when used in medical devices,” added Dr. Brouard.

The potential applications of this research are vast. By preventing bacterial adhesion and proliferation, PDA coatings can significantly reduce the incidence of HAIs, leading to safer medical procedures and improved patient outcomes. The researchers suggest that future work should focus on enhancing the antibacterial properties of PDA through chemical modifications and functionalization.

This study represents a significant step forward in the development of antibacterial materials for medical applications. By optimizing the synthesis and application of PDA coatings, Dr. Brouard and his colleagues have paved the way for new strategies to combat HAIs and improve healthcare safety.

Journal Reference

Fonseca, S., Fontaine, N., Cayer, M.-P., Robidoux, J., Boudreau, D., & Brouard, D. (2024). Synthesis and antibacterial properties of unmodified polydopamine coatings to prevent infections. Next Materials, 3, 100161. DOI: https://doi.org/10.1016/j.nxmate.2024.100161

About The Authors

Sahra Fonseca, MSc, is a research professional in the Research Department at Héma-Québec. After completing a BSc in microbiology in 2019, she received her master’s degree in biochemistry in 2021 from Université Laval for the evaluation of the antibacterial and anti-adhesive properties of a nanoparticle coating for biomedical applications. Her research mainly focuses on the topics of nanomaterials, polymers and the quality and safety of blood products.

Nicolas Fontaine, PhD, is a postdoctoral fellow in the research group of Philippe Dauphin Ducharme in the Department of Chemistry at Université de Sherbrooke. After completing a BSc in chemistry with honors in 2017, he received his PhD in 2022 from Université Laval for his thesis on the development of highly luminescent nanosensors for the detection of metabolites of the gut microbiota. He then moved to Sherbrooke to begin training in electrochemistry. His research focuses on the topics of nanomaterials, optical and electrochemical sensors. Nicolas ‘research is currently supported by FRQNT and aims to enhance the analytical performances of electrochemical aptamer-based biosensors to facilitate their deployment in real-life applications.

As part of their studies at Université Laval, Nicolas and Sahra were called upon to work together by promoting the sharing of their respective expertise. This collaboration further highlights the significant synergy of Héma-Québec’s achievements in microbiology and blood products, as well as Professor Boudreau’s laboratory for its experience in the instrumentation and characterization of nanomaterials. Together, they demonstrated the importance of this collaboration for the continued development of active materials and analytical methods in the field of microbiology.