Bacterial Nanocellulose and Its Surface Modification by Glycidyl Methacrylate and Ethylene Glycol Dimethacrylate. Incorporation of Vancomycin and Ciprofloxacin

Abstract

Among nanocelluloses, bacterial nanocellulose (BNC) has proven to be a promising candidate in a range of biomedical applications, from topical wound dressings to tissue-engineering scaffolds. Chemical modifications and incorporation of bioactive molecules have been obtained, further increasing the potential of BNC. This study describes the incorporation of vancomycin and ciprofloxacin in BNC and in modified BNC to afford bioactive BNCs suitable for topical wound dressings and tissue-engineering scaffolds. BNC was modified by grafting glycidylmethacrylate (GMA) and further cross-linking with ethylene glycol dimethacrylate (EGDMA) with the formation of stable C–C bonds through a radical Fenton-type process that involves generation of cellulose carbon centred radicals scavenged by methacrylate structures. The average molar substitution degree MS (MS = methacrylate residue per glucose unit, measured by Fourier transform infrared (FT–IR) analysis) can be modulated in a large range from 0.1 up to 3. BNC-GMA, BNC-EGDMA and BNC-GMA-EGDMA maintain the hydrogel status until MS reaches the value of 1. The mechanical stress resistance increase of BNC-GMA and BNC-GMA-EGDMA of MS around 0.8 with respect to BNC suggests that they can be preferred to BNC for tissue-engineering scaffolds in cases where the resistance plays a crucial role. BNC, BNC-GMA, BNC-EGDMA and BNC-GMA-EGDMA were loaded with vancomycin (VC) and ciprofloxacin (CP) and submitted to release experiments. BNC-GMA-EGDMA of high substitution degree (0.7–1) hold up to 50 percentage of the loaded vancomycin and ciprofloxacin amount, suggesting that they can be further investigated for long-term antimicrobial activity. Furthermore, they were not colonized by Staphylococcus aureus (S.A.) and Klebsiella pneumonia (K.P.). Grafting and cross-linking BNC modification emerges from our results as a good choice to improve the BNC potential in biomedical applications like topical wound dressings and tissue-engineering scaffolds.

Latest Advances on Bacterial Cellulose-Based Antibacterial Materials as Wound Dressings

“…Immersion method is the common method of combining BC with antibiotics, which is simple and easy to operate but may cause uneven distribution of antibiotics. For example, vancomycin and ciprofloxacin can be incorporated into bacterial nanocellulose (BNC) or modified BNC to provide bioactivity for wound dressing and tissue engineering scaffold (Vismara et al, 2019). The BC composite materials containing amikacin and ceftriaxone were prepared by immersing the dried BC films in different concentrations of antibiotics solution.…”

Modifications of bacterial cellulose in wound care

“…It was reported that BC dressings impregnated with these antibiotics effectively impede infection development. 33 A high bactericidal effect of vancomycin and ciprofloxacin was determined against S. aureus spp. and K. pneumoniae spp.…”

Nisin-Loaded Bacterial Cellulose: Evaluation of Its Antimicrobial Activity Stability

“…This result shows that nisin was absorbed by CB membranes, and after 4 hours maximum release was reached and maintained, which may be used as a strategy to minimize the time of reapplications. Retention and consecutive release are reported in several studies with molecules and drugs, mainly with potential antimicrobials, where they try to maintain this release in a controlled manner [34]. CB provides ideal retention, with structural and functional protein stabilization, due to its nanofiber structure [24].…”