Page 142 - IJB-9-6

International Journal of Bioprinting 3D printed bioactive dressings for burn wound treatment

rate and ion release from BBG make it highly reactive, multiple materials and geometries . Our previous research
[59]
which can damage the fragile wound bed in the case of showed that 3D-printed dressings with an adequate
burn wounds . On the other hand, the burst release of gelatin/alginate ratio promote burn wound healing . We
[49]
[51]
therapeutic ions from BBG can increase the local pH to highlighted that the 3D-printed porous surface supports
alkaline range, which can cause local toxicity and tissue non-adhesive contact and increases the available surface
damage. An effective approach to address this challenge for wound-dressing interactions compared to non-
is to incorporate BBG particulates in natural hydrogel printed dressings of the same composition. However,
matrices. The BBG–hydrogel complex can take advantage wound dehydration remains a major clinical challenge in
of the synergistic activity of therapeutic ions from BBG burn wound treatment. In the research, we incorporated
and the soothing effect of the hydrogels, making it 3D-printed hydrogel dressings with BBG, which allows for
effective for burn wounds. While the hydrogels provide controlling the release of water and therapeutic ions as well
water for wound hydration, BBG particulates prevent as enhancing the dressing fixity on the wound for longer
the burst release of water molecules from the hydrogel time. To the best of our knowledge, the current research
network, making it stable on the wound surface for longer investigates the use of 3D-printed glass-hydrogel wound
time periods. dressings for the first time.

Hydrogels are large 3D molecules composed of In this study, 3D-printed dressings with gelatin,
hydrophilic polymer chains that absorb and retain large alginate, and various amounts of BBG were fabricated and
amounts of water . Hydrogels are an essential class of characterized to enhance the functionality of burn wound
[50]
advanced wound dressings that can donate or absorb water care products. After measuring the mechanical properties,
in accordance with the wound condition [7,51,52] . Since 1977 degradation rate, hydration activity, water release rate,
when hydrogels were introduced as wound dressings for and in vitro biocompatibility, an in vivo wound healing
the first time , their biological performance has been study was conducted to investigate the effect of BBG and
[53]
enhanced by adding glass materials, peptides, and growth 3D-printed porous contact on treatment of second-degree
factors [54-56] . In 2019, Zhu et al. incorporated ZnO/silicate burn wounds using a rat model. BBG powder, non-printed
glass and epidermal growth factor (EGF) into alginate/ hydrogels of the same formulation, and a commercial
chitosan hydrogel compound. Their results showed that the product were included in the experiment.
ZnO/silicate glass promoted the formation of granulation
tissue, deposition of collagen and myofibril, release of anti- 2. Materials and methods
inflammatory factors, angiogenesis, and wound closure .
[57]
In 2020, Zhu et al. showed that silicate glass/alginate 2.1. Materials
compound can modulate the inflammatory response Gelatin type B (from bovine skin, gel strength: 225
[52]
and angiogenesis . Chen et al. incorporated GelMa g Bloom), sodium alginate (alginic acid sodium salt
with cerium-doped silicate glass to develop an injectable from brown algae, medium viscosity), calcium chloride
compound for treatment of diabetic ulcers. Their results anhydrous, Dulbecco’s Modified Eagles Medium (DMEM),
showed that cerium-doped glass improved the angiogenesis phosphate-buffered saline (PBS), fetal bovine serum (FBS),
and antibacterial activity of the hydrogel by regulating 1% penicillin/streptomycin (pen/strep), MTT, and trypsin/
the anti-inflammatory response . In another research EDTA were purchased from Sigma-Aldrich (St. Louis,
[28]
published in 2022, Mehrabi et al. developed in situ forming Missouri, USA). BBG (particle size <20 µm) was provided
hydrogel dressing by incorporation of borate glass into by ETS Wound Care (Missouri, USA). All materials were
chitosan/carboxymethyl cellulose hydrogel compound. used as received without further modification.
Their results showed consistent angiogenesis, remodeling, 2.2. Bioink preparation
[58]
and accelerated wound healing in diabetic rats . Although In this study, the gelatin:alginate ratio of 5:3 was selected
the use of novel hydrogels incorporated with bioactive as the primary hydrogel matrix based on our previous
glass has paved the road for effective wound treatment, the findings, which demonstrated the optimal balance in terms
majority of these hydrogel dressings are amorphous gels of mechanical properties, printability, and biocompatibility
with poor mechanical stability on the wound and short- in this hydrogel compound . To prepare the hydrogel–
[16]
term wound coverage. These shortcomings may result BBG bioinks, different concentrations of BBG (0, 10,
in frequent change of wound dressing that cause pain and 20 wt% of dry material) were mixed with 7 mL of
and infection. deionized (DI) water and vigorously stirred for 24 h at
3D printing, as a rapidly developing manufacturing room temperature. After centrifuging and filtering, the
technology, enables the programmable and customizable resulting supernatants were mixed with 500 mg of gelatin
high-throughput fabrication of wound dressings with powder and stirred for 10 min at 40°C to obtain 5% (w/v)

Volume 9 Issue 6 (2023) 134 https://doi.org/10.36922/ijb.0118