Page 186 - IJB-9-5

International Journal of Bioprinting Functional materials of 3D bioprinting for wound healing

Table 2. 3D-bioprinted skin wound dressings for wound healing applications
Main components Representative functional materials Properties for accelerating wound healing Ref.
Gel/Alg/HA/PPV PPV Antibacterial [130]
GMA/CMC/ε-PL ε-PL Antibacterial, antioxidant [128]
GelMA/CMC/Xanthan gum/CeO / APSGH-Cl Antibacterial [131]
2
N-halamine (APSGH-Cl)
Gel/AgNO AgNO Antibacterial [132]
3 3
AgNW/MAA AgNW/MAA Antibacterial, conductive, flexible [133]
HA/SiO /CINP SiO /CINP Antitumor, antioxidant, antibacterial [134]
2 2
CNC/Chit-MA/Gentamicin/AgNPs AgNPs Antibacterial [135]
PEGDA/Gallium maltolate (GaM) GaM Antibacterial [136]
PAM/HPMC/AgNPs AgNPs Antibacterial [137]
N-halamine (PSPH-Cl)/TiO /GelMA/ PSPH-Cl Antibacterial [138]
2
Xanthan gum
GO-CS-Calcium silicate CS Antitumor, antibacterial [19]
Abbreviations: Alg, alginate; AgNPs, silver nanoparticles; AgNW, silver nanowire; Chit-MA, chitosan methacrylamide; CINP, nanoparticle derived from
cuttlefish ink; CMC, carboxymethylcellulose sodium; CNC, cellulose nanocrystal; CS, chitosan; ε-PL, ε-polylysine; GaM, gallium maltolate; Gel, gelatin;
GelMA, gelatin methacryloyl; GMA, glycidyl methacrylate; GO, graphene oxide; HA, hyaluronic acid; HPMC, hydroxypropyl methylcellulose; MAA,
methacrylic acid; PAM, polyacrylamide; PEGDA, poly(ethylene glycol)-diacrylate; PPV, polyphenylene vinylene derivative;
The results of LIVE/DEAD staining indicated that ePatch thickness wound skin regeneration due to their unique
enhanced the proliferation and migration of NIH 3T3 properties. Therefore, combining functional materials
fibroblasts by electrical stimulation (Figure 5d). A rat (antibacterial materials, antioxidant, hemostatic materials,
model of full-thickness wound repair demonstrated that flexible material, and antitumor material) and bioactive
the soft and stretchable ePatch fitted tightly to the rats molecules (cell-binding peptides, growth factors, bioactive
curved back and shortened the wound healing time to only nanoparticles, and other specific additives) with 3D
7 days, significantly promoting wound closure (Figure 5e bioprinting technology can produce functionalized
and f). In addition, antimicrobial performance testing skin substitutes that maintain tissue homeostasis, thus
showed the ability of ePatch to prevent Gram-positive and providing a new strategy for on-demand preparation
Gram-negative infections both in vitro and in vivo. This of multifunctional hydrogels in the area of skin tissue
3D bioprinting-based multifunctional biomaterial system engineering [154] .
with antibacterial, conductive, and soft properties provides When the skin is injured, microbes can easily irrupt the
a new approach to promote wound healing. Table 2 wound and arouse serious infections that hinder wound
summarizes the reports of 3D-bioprinted antibacterial healing [42,128] . The general solution is to encapsulate metal
wound dressing used for wound healing. The addition of nanomaterials, antibiotics, and/or antibacterials into
various functional materials has promoted the design and scaffolds to prevent and treat wound site infections .
[42]
innovation of 3D-bioprinted wound dressings.
Wan et al. fabricated a bilayer scaffold with silver-loaded
[25]
5.2. Skin tissue engineering scaffolds gelatin cryogel as the top layer and platelet-derived growth
Skin tissue engineering is a complex process that involves factor-BB (PDGF-BB)-loaded 3D-printed gelatin as the
mimicking the tissue-specific microenvironment of native bottom layer (Figure 6a). This bilayer design is designed
tissue [116] . Traditional tissue-engineered skin scaffolds to protect the wound from infection through the release
are usually made of live cell-loaded natural or synthetic of silver nanoparticles in the upper layer, while delivering
materials, which are easily limited by the printability growth factors that adjust cell growth and division to the
and biocompatibility of the materials [152] . 3D bioprinting granulation tissue of the wound bed through the basal
technology has been extensively used in the fabrication layer. A diabetic mouse wound model showed that PDGF-
of organs, tissues, and blood vessels because of its ability BB-loaded scaffolds could accelerate granulation tissue
to accurately simulate living cells in confined spatial formation, neovascularization, and collagen deposition
configurations to generate complex tissue analogs [128,153] . (Figure 6b).
Furthermore, functional materials have important clinical The microenvironment around the damaged skin
value in accelerating wound healing and inducing full- is harsh, and a large amount of ROS will accumulate in

Volume 9 Issue 5 (2023) 178 https://doi.org/10.18063/ijb.757