Resistance to bacterial biofilms, organic membranes formed of microorganisms embedded in a self-made polymeric matrix, has long been the subject of antimicrobial adhesion research. Infections related to biomaterials are usually caused by the production of biofilms. One of the most important variables determining eventual fouling biological adhesion is the creation of early biofilms by bacteria combined with organic substances.
Alfa Chemistry's research has focused on biomaterials modified by nanomaterial types with antimicrobial properties. We improve the antimicrobial properties of substrates through chemical surface modification. Our research and application of chemical surface modification of polymeric biomaterials are effective and fruitful. If you would like to quickly modify the surface of your product for biomedical applications, please contact us.
Anti-Fouling Surface Technology Platform
Despite the fact that many strategies exist to prevent bacterial adhesion, pathogenic biofilm formation remains a major cause of biomaterial-associated infections, and Alfa Chemistry can assist customers in resisting microbial surface adhesion using appropriate chemical surface modification techniques. More information on surface modification techniques can be found in the following.
| Strategies | Grafting | Methods | Results |
|---|
| Immobilize PEG derivatives | PEG with terminal hydroxyl, amino and sulfonate groups | Grafting of PEG with terminal functional groups onto PU surfaces | Reduced adhesion of Staphylococcus epidermidis and Escherichia coli in plasma and culture medium |
| Copolymers of methacrylate-containing PEG and fluoroalkyl acrylates | The copolymer was grafted to cross-linked PDMS coating | Has highly effective antifouling and decontamination properties, exhibiting spontaneous spore removal in some cases |
| Graft amphiphilic polymers | p(N-hydroxy ethylacrylamide) (PHEAA) postmodified by fluorinated segments | Grafting of PHEAA brushes from the substrate surface via SI-ATRP | It has efficient and long-lasting bacterial anti-adhesion properties |
| Mannoside-poly(amido amine) (PAMAM) dendrimers | Preparation of propynyl phenyl mannoside aglycones attached to nanometer amino-terminated PAMAM dendrimers on silicone surfaces | Improve catheter remodeling efficiency, non-pathogenic biofilm coverage, and (long-term) stability to prevent uropathogen infection. |
| Graft ionic polymers | Cationic N,N-dimethyl-2-morpholinone (CB-Ring) and zwitterionic carboxy betaine (CB-OH) | Immobilize CB-Ring and CB-OH onto substrate surfaces to form a smart polymer coating | Achieve attacking and defending functions in a controlled manner, kill and release bacteria, further resist adhesion of bacteria |
| Biocides | Chitosan | Chitosan was immobilized with acrylamide-grafted glutaraldehyde (GA) crosslinker | The PET substrate exhibits limited antimicrobial activity against Candida albicans |
Because of their hydrophilic and non-toxic nature, previous chemical surface modification research has concentrated on immobilizing PEG derivatives on polymeric biomaterials. However, because PEG does not kill germs, its antibacterial effects deteriorate over time. As a result, Alfa Chemistry employs PEG-b-cationic polymers as antibacterial and antifouling coating modifiers.
Fig 1. Schematic representation of brush-like polycarbonates containing dopamine groups, cations, and PEG chains providing a broad-spectrum, antibacterial, and antifouling surface via one-step coating. (Yang C, et al. 2014)
For example, an antimicrobial surface was prepared in one step by immersing the catheter surface in a brush polycarbonate (containing a side gum dopamine moiety, antifouling PEG chains, and antimicrobial cations). The coating has outstanding antibacterial and antifouling activity against Gram-positive and Gram-negative bacteria, proteins, and platelets, as well as good stability and minimal biotoxicity under simulated blood flow circumstances.
In order to acquire antibacterial and anti-biofouling capabilities, we grafted poly(ionic liquid) (PIL) onto the hybrid material. We also selected grafted stimuli-responsive materials for antimicrobial adhesion, such as thermal-responsive, pH-responsive, and light-responsive polymers. Bovine Serum Albumin is a low-cost, commonly available protein. Because of its excellent anti-adherence to platelets, mammalian cells, and erythrocytes, we fabricated the BSA-mediated anti-adherent surface against oral bacteria to combat oral germs. The BSA-modified surface has higher antimicrobial properties, which is due to the anti-adhesion ability of BSA rather than bactericidal and release effects.
Fig 2. The antiadhesion behavior of oral bacteria on the BSA-modified surface of oral fixed appliances pretreated FAS. A) The chemical modification process of oral fixed appliances. B) The antibacterial behavior results from the antiadhesion capability of the BSA molecules. (Liu X, et al. 2018)
References
- Yang C, et al. (2014). "Brush-Like Polycarbonates Containing Dopamine, Cations, and PEG Providing A Broad-Spectrum, Antibacterial, and Antifouling Surface via One-Step Coating." Adv Mater. 26(43): 7346-7351.
- Liu X, et al. (2018). "Protein-Mediated Anti-Adhesion Surface against Oral Bacteria." Nanoscale. 10: 2711-2714.
