Amphiphilic hydrogels functionalized with antimicrobial peptides for wound care
Doktorsavhandling, 2023
The aim of this thesis was to investigate the covalent attachment of AMPs to the surface of Pluronic F127 based amphiphilic hydrogels and validate the same in vitro, in vivo, and clinically for wound care applications. A few variants of the material were created, with hydrogel discs being the most common as a convenient base for evaluation. The material was also prepared as a wound dressing where it was evaluated in a human intact skin study for a clinically relevant investigation. Furthermore, the material was also made into particles as a platform for treating deeper wounds as well as in liquid formulation or as a coating.
Overall, the AMP-functionalized hydrogels showed a potent antibacterial activity against both gram-negative and gram-positive bacteria, and some antibiotic resistant strains among them. At the same time, the materials did not show any signs of cytotoxicity against fibroblasts or erythrocytes. Furthermore, the AMP-functionalized hydrogels showed a potential to reduce the endotoxin levels released by Pseudomonas aeruginosa, a property that might assist further with combating the adverse effects of a wound infection and improve healing outcomes. The material also showed a significant antibacterial effect against the bacteria naturally present on our skin when evaluated clinically on healthy volunteers.
A main limitation behind the clinical use of AMPs is that they have a low biostability and are rapidly degraded by proteolytic enzymes. By covalently attaching the AMPs to a solid substrate they should gain steric protection against degradation. That was also the case observed for the AMPs when covalently attached to the hydrogels, as they retained their antibacterial activity for several days, both in serum, and implanted in an infected rat model. The covalent attachment of the AMPs also resulted in a contact killing mechanism, suitable for a local antibacterial effect.
infections
Antimicrobial peptides
hydrogels
wound care
lyotropic liquid crystals
antibacterial surfaces
amphiphilic polymers
surface functionalization
Författare
Edvin Blomstrand
Chalmers, Kemi och kemiteknik, Tillämpad kemi
Antimicrobial Peptide-Functionalized Mesoporous Hydrogels
ACS Biomaterial Science and Engineering,;Vol. 7(2021)p. 1693-1702
Artikel i vetenskaplig tidskrift
Cross-linked lyotropic liquid crystal particles functionalized with antimicrobial peptides
International Journal of Pharmaceutics,;Vol. 627(2022)
Artikel i vetenskaplig tidskrift
Clinical investigation of use of an antimicrobial peptide hydrogel wound dressing on intact skin
Journal of Wound Care,;Vol. 32(2023)p. 368-375
Artikel i vetenskaplig tidskrift
Blomstrand, E, Posch, E, Stepulane, A, Rajasekharan, A.K, Andersson, M. Antibacterial and hemolytic activity of antimicrobial peptides in solution and attached to a hydrogel surface
Blomstrand, E, Atefyekta, S, Rajasekharan, A.K, Svensson, S, Trobos, M, Thomson, P, Andersson, M. In vivo biostability and endotoxin binding properties of a hydrogel functionalized with antimicrobial peptides
En fantastisk källa till inspiration är att undersöka hur naturen löser ett problem. Ett ämne som återfinns i de flesta flercelliga organismers medfödda immunförsvar är antimikrobiella peptider. Dessa peptider är specialister på att döda bakterier på ett sådant sätt att det inte skadar våra egna celler, och har mycket lägre risk att orsaka resistens. Tyvärr finns det vissa nackdelar med antimikrobiella peptider då de bryts ned snabbt i biologiska miljöer. I denna doktorsavhandling undersöks därför en metod där peptiderna binds in till ytor som skyddar peptiderna samtidigt som de fortfarande kan utöva sin bakteriedödande effekt. Detta resulterar i ett antibakteriellt material som lämpar sig för användning inom sårvård för att motverka infektioner och tillåta en naturlig läkning.
Ämneskategorier
Materialteknik
ISBN
978-91-7905-912-5
Doktorsavhandlingar vid Chalmers tekniska högskola. Ny serie: 5378
Utgivare
Chalmers
10:an
Opponent: Georgios Sotiriou, Karolinska Institutet, Stockholm, Sweden.