properties for in vitro culture and in vivo implantation. Indeed, the
low viscosity of the deposited fluid and the time necessary for its
gelation often lead to low reproducibility, control, and resolution of
the filament structure.
The authors have disclosed [7] the use of heat-sensitive hydrogels characterized by a sol-gel transition in a temperature range
between 20
C and 30
C to prepare cell-laden constructs which are
particularly stable under physiological conditions.
In the present work, the Pluronic/alginate gel system has been
proposed as a prototypal thermosensitive gel to describe the procedure for the fabrication of cell-laden constructs with controlled 3D
structure. This combination of polymers with distinct phasetransition mechanisms has been chosen with the aim of integrating
the advantages of Pluronic gel in terms of printability [8] with the
stability of the temperature-insensitive alginate component. The
present system has been tested in combination with several cell
lines (BALB/3 T3, C2C12, and Human Dermal Fibroblast)
[9, 10] and successfully adopted for the engineering of muscle
cell alignment through the use of C2C12 murine myoblast cell
line [9].
2 Materials
To minimize the risk of contamination, AM equipment should be
placed in a biological safety cabinet, and all the pieces of equipment
in contact with the bioink should be properly sterilized before
processing.
2.1 Preparation
of the Bioink
1. Pluronic F127 (BASF).
2. Sodium alginate (PROTANAL
®
XP 3499, FMC
BioPolymers).
3. Dulbecco’s Modified Eagle Medium (DMEM).
4. Deionized water.
5. Autoclavable glass vial with lid and magnet.
6. Cell source (e.g., human dermal fibroblasts from adult skin,
HDF) with appropriate medium and supplements.
7. Autoclave.
8. Ice bath.
9. Magnetic stirrer.
2.2 Additive
Manufacturing
1. A three-axes motion control system (see Note 1).
2. Pressure-driven syringe barrel and piston system (Optimum
system, Nordson EFD) terminated with a 250 μm ID blunt
needle.
138
Sara Maria Giannitelli et al.
low viscosity of the deposited fluid and the time necessary for its
gelation often lead to low reproducibility, control, and resolution of
the filament structure.
The authors have disclosed [7] the use of heat-sensitive hydrogels characterized by a sol-gel transition in a temperature range
between 20
C and 30
C to prepare cell-laden constructs which are
particularly stable under physiological conditions.
In the present work, the Pluronic/alginate gel system has been
proposed as a prototypal thermosensitive gel to describe the procedure for the fabrication of cell-laden constructs with controlled 3D
structure. This combination of polymers with distinct phasetransition mechanisms has been chosen with the aim of integrating
the advantages of Pluronic gel in terms of printability [8] with the
stability of the temperature-insensitive alginate component. The
present system has been tested in combination with several cell
lines (BALB/3 T3, C2C12, and Human Dermal Fibroblast)
[9, 10] and successfully adopted for the engineering of muscle
cell alignment through the use of C2C12 murine myoblast cell
line [9].
2 Materials
To minimize the risk of contamination, AM equipment should be
placed in a biological safety cabinet, and all the pieces of equipment
in contact with the bioink should be properly sterilized before
processing.
2.1 Preparation
of the Bioink
1. Pluronic F127 (BASF).
2. Sodium alginate (PROTANAL
®
XP 3499, FMC
BioPolymers).
3. Dulbecco’s Modified Eagle Medium (DMEM).
4. Deionized water.
5. Autoclavable glass vial with lid and magnet.
6. Cell source (e.g., human dermal fibroblasts from adult skin,
HDF) with appropriate medium and supplements.
7. Autoclave.
8. Ice bath.
9. Magnetic stirrer.
2.2 Additive
Manufacturing
1. A three-axes motion control system (see Note 1).
2. Pressure-driven syringe barrel and piston system (Optimum
system, Nordson EFD) terminated with a 250 μm ID blunt
needle.
138
Sara Maria Giannitelli et al.