Advanced Strategies for Biofilm Prevention and Disruption: Materials, Coatings, Nanotechnologies, and Predictive AI Models

Dear Colleagues,

In this Special Issue, we welcome original research papers and reviews focused on the complex relationships between biofilms and solid surfaces.

Biofilm is a community of microorganisms (bacteria, fungi, algae, etc.) that adhere to a surface and are wrapped in a matrix of extracellular polymeric substances (EPS). This structure gives them increased resistance to antimicrobial agents and host defenses.

(1) Scientific Background

Characteristics of the biofilm:

• Adhesion: Microorganisms attach to a solid surface (metal, plastic, biological tissues).
• Protective matrix: They produce an extracellular substance that protects them from external aggression.
• Communication: Cells communicate with each other through a mechanism called "quorum sensing".
• Increased resistance: Bacteria in a biofilm can be up to 1000 times more resistant to antibiotics than free (planktonic) bacteria.

(2) Examples of biofilms:

• Dental plaque (Streptococcus mutans, Porphyromonas gingivalis).
• Biofilms on medical implants (prostheses, catheters, stents), formed on metal, plastic, ceramic, or coated surfaces.
• Biofilms in the food industry and drinking water (bacterial contamination).

(3)  Biofilms are problematic on medical devices:

• Biofilms adhere to the surfaces of devices such as stents, valves, probes, endoprostheses, etc.
• They are highly resistant to conventional antibiotics and often escape the body’s immune response.

(4) Biofilm issues:

• Persistent and difficult to treat infections.
• Accelerated corrosion of metal surfaces (e.g., implants, pipelines).
• Impaired medical performance of implantable devices (stents, prostheses).
• A rapid recolonization after treatment.
• The failure of the device, requiring its removal or replacement.

(5) Biofilm is a major challenge due to its increased resistance to antibiotics and disinfectants.

Fighting with Biofilm has two important sides:

1. Prevent formation of Biofilm and b. Destroy the Biofilm once it has appeared.
2. How to prevent a biofilm? In surgeries, adjuvant materials are necessary to aid intraoperative technique and prevent the formation of biofilm.

A good anti-biofilm material often has one or more of these effects:

- Prevents bacterial adhesion (super-hydrophobic or textured surface).         

- Releases an antimicrobial agent (silver, copper, peptides, etc.).

- Kills bacteria upon contact (cationic surface, nanostructured).

- Disrupts bacterial communication (quorum sensing blockers).

(6) Biofilm-related infections on implantable devices represent a major challenge during surgical interventions. To deepen the strategies for eliminating biofilms in this context, we propose a selection of relevant scientific themes to be addressed in this Special Issue:

6.1. Coatings surface treatments:

             o Non-stick coatings (hydrophilic, no releasing, etc.).

             o Innovative nanocoatings.

             o Antimicrobial materials:

               - Incorporation of silver, copper, zinc, nanoparticles.

               - Integration of antibiotics into the polymer or metal protective layers.

6.2 Nanoengineering of multifunctional titanium implant surfaces.

6.3 Antifouling micro-nanostructured biomaterials.

6.4 Mechano-bactericidal nanostructured biomaterials surfaces.

6.5 Nanocoating of antifilmogenic activity, hydrophobic surfaces, graphene, cationic polymers, ceramic, etc.

6.6 Multifunctional antimicrobial-releasing bioactive ceramics and glasses.

6.7 Bioactive glass releasing phytotherapeutic molecules.

6.8 Amorphous calcium and phosphate-based materials (CaP).

6.9 Crystalline CaP and related composites.

6.10 Natural polymers as multifunctional antimicrobial platforms.

6.11 Surface grafting of antimicrobial agents by electrophoretic deposition.

6.12 Biophysical agents that can destroy in vivo the biofilm. Interaction of these agents with metallic implants.

6.13 Biochemical agents that can destroy in vivo the biofilm. Interaction of these agents with implants.

(7) Contributions of artificial intelligence (AI), biofilm + quantum computing

Creating anti-biofilm surfaces or materials is a strategic area of research, particularly in the fields of medicine, agri-food, and industrial devices. The idea is to prevent the adhesion of bacteria or block the formation of biofilm from the first steps.

• Predict the formation of biofilms according to conditions and materials.
• Identify critical parameters (pH, nutrients, roughness, etc.).
• Optimize the design of less colonizable coating surfaces.
• Exploration of new material combinations with quantum optimization algorithms.
• Modeling of the behavior of biomolecules on a surface (protein adhesion).

We hope that this Special Issue can highlight many exciting innovations in the field of antimicrobial biomaterials through your publications. Despite the excellent data on antimicrobial efficacy—especially in light of the ongoing threat of antimicrobial resistance—many cases still require more extensive testing in complex system models to critically evaluate antimicrobial activity in conjunction with the relevant tissue interactions and host immune responses. We look forward to receiving your contributions.

Prof. Dr. Lucien Reclaru
Prof. Dr. Dan Cristian Grecu
Guest Editors

Manuscript Submission Information

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• biofilms
• biofilms on medical implants (metal, ceramic, plastic)
• biofilms in the food industry
• destroying a biofilm
• destroying a biofilm in vivo
• electromagnetic field and biofilm
• anti-biofilm coatings on implant (metal, ceramic, plastic)
• nanotechnology and new strategies
• antimicrobial nanoparticles
• silver (AgNPs) and copper (CuNPs) to prevent bacterial adhesion.
• nanoceramic with antibiotic release.
• antimicrobial peptides (AMPs) coating materials
• bacteriophages coating materials
• AI and quantum machine learning (QML)
• quantum chemistry simulations (e.g., Hartree–Fock, DFT)
• new material combinations with QML algorithms
• modeling the behavior of biomolecules on a surface
• quantum simulators (Qiskit chemistry)
• regulatory aspects