Page 45 - IJB-9-1

International Journal of Bioprinting Effect of ionic crosslinking on composite membranes

either by chemical or ultraviolet (UV) crosslinking to designed and prepared. The bioscaffold was applied to
enhance the mechanical properties of the constructs. design a series of composite bioscaffolds for bioprinting
Depending on the type of polymer used in the bioink, applications. Furthermore, the morphology, structural
biological tissues and scaffolds of varied complexity can stability, and thermostability of the resulting biomimetic
be fabricated . Alginate is a natural polysaccharide that supercritical fluids-decellularized dermal-based
[2]
typically originates from various species of algae. Due to its composite bioscaffolds were studied to provide another
low cost, good biocompatibility, and rapid ionic gelation, valuable view for bioprinting applications. Supercritical
the alginate hydrogel is a good option of bioink source for carbon dioxide (ScCO ) was employed to prepare a
2
3D bioprinting. However, the lack of cell adhesive moieties kind of supercritical fluids-decellularized dermal-
was the critical limitation of alginate hydrogel bioink . based bioscaffold (SFDDS). In the previous works,
[8]
supercritical fluid-based decellularization protocols were
For natural material, collagen is the most abundant
protein in animals and has been widely used in the shown to have great advantage over the conventional
decellularization as it may allow preservation of
[9]
biomedical applications as a biomaterial . Decellularized extracellular matrix components and structures . The
[1]
matrix containing collagen segments is considered a ScCO decellularization would significantly reduce
desirable bioscaffold for tissue regeneration because the treatment times, achieve complete decellularization, and
2
decellularized matrix maintains the original components preserve extracellular matrix structure. The rupture of
of native tissue, which could constitute the main structural the cells as a result of high pressure of the fluid during
element to provide biocompatibility, structural stability, the treatment and rapid depressurization is expected
physical and structural configuration, cell adhesion, and to be effective in removing the cells from the tissues .
[1]
cell migration for direct tissue development in bioprinting The resulting SFDDS was introduced into the alginate-
applications [10,11] . The decellularized bioscaffold could based bioink. A series of new alginate-based composite
be obtained and purified by a combined procedure bioscaffolds containing SFDDS were designed and
with decellularizing and defatting, such as supercritical obtained. The new design of composite bioscaffolds
fluid treatments, chemical treatments, and enzyme has high stability and excellent biological properties
treatments . Supercritical fluids could extract the fat of the scaffolds in orthopedics and gene therapy. The
[12]
without damaging and affecting the collagen segments. composite bioscaffolds containing collagen scaffolds
Furthermore, the supercritical fluids could be employed were characterized by Fourier transform infrared
at a critical temperature of 31°C, which was low enough (FTIR), scanning electron microscopy (SEM), and
for processing collagen. Supercritical fluids could provide thermogravimetric analysis (TGA) to obtain the results
a good and clean choice for decellularizing and defatting on thermostabilities and morphology. Effect of ionic
procedures which have outstanding properties, such crosslinking reaction with various crosslinking time on
as being non-corrosive, non-toxic, and non-flammable structural stability and thermal stability of the resulting
property [13-15] . For natural material, sodium alginate, which composite bioscaffolds was further studied.
was extracted from marine brown algae [16,17] , has a wide
range of biomedical and bioprinting applications, such as 2. Materials and methods
cell immobilization and tissue regeneration [18-20] .
2.1. Materials
Extrusion-based three-dimensional (3D) bioprinting
strategies are widely used for producing 3D tissue Chemicals utilized in the present study include sodium
alginate (Sigma-Aldrich Company), sodium hydroxide
constructs. This technology has rapidly evolved over the (Sigma-Aldrich Company), Triton X-100 (Sigma-Aldrich
past two decades, providing a powerful tool set for the Company), calcium chloride (CaCl , Fluka Company),
biofabrication of tissues that can facilitate translational 0.5M acetic acid, 20% alcohol, sodium dihydrogen
2
[21]
efforts in the field . Several studies have been conducted phosphate, and disodium hydrogen phosphate (First
to explore suitability of extrusion bioprinting in the aspects Chemical Works Company).
of rheological property, printability and biocompatibility,
which could provide many valuable information for 2.2. Preparation of SFDDS
bioprinting application . Further, computer-aided Before enzyme treatment being used for removing most
[21]
processes have been studied and used to build up new 3D fatty acids and tissues of raw porcine dermal, the ScCO
bioprinting strategies, which would play an important role was employed to prepare a new scaffold at 45°C and 18
2
for 3D bioprinting application . mPa for 6 h. Furthermore, raw porcine dermal samples
[22]
In this study, a new biomimetic decellularized were treated at 25°C by aqueous sodium hydroxide solution
dermal-based bioscaffold for extrusion bioprinting was (2 wt %) for 2 h and followed by aqueous Triton X-100

Volume 9 Issue 1 (2023) 37 http://doi.org/10.18063/ijb.v9i1.625