[4]. Dispersion of Laponite in an aqueous environment results in a
colloidal suspension of clay nanoparticles, which can associate to
form gels via both repulsive and attractive interactions depending
on solid concentration and the ionic concentration of the solution
[5, 6].
Laponite has several functional properties, including (1) shear
thinning and thixotropic behavior [7], (2) retention or localization
of drugs due to strong protein-clay interactions [8], and (3) cell
stimulation [9], as well as its widespread use in polymer clay nanocomposites. Due to the physical nature of Laponite interactions,
nano-colloids and composites often display shear thinning or selfhealing properties which can be particularly useful for cell printing
processes [10].
Bioinks (biomaterials blended with living cells) have recently
come to the fore in regenerative medicine, given their versatility
and functional potential to deliver living cells in 3D, within discrete
tailored architecture and/or highly ordered cell-laden structures.
Biofabrication can generate large-scale structures with a plethora of
biomaterials. Nevertheless, bioinks that can elicit a degree of functional stimulation toward the encapsulated cells remain to be developed. Clay-based hydrogels can be tuned to retain or localize drugs
after brief exposure, stimulating angiogenesis [8] or bone formation [11] illustrating the clinical potential and opportunity
provided by Laponite and related materials to provide a one-step
procedure to encapsulate, retain, and deliver therapeutic agents
[8]. Moreover, recent advances [9] have investigated the direct
effect that Laponite nanodispersion can have on human mesenchymal stem cells (hMSCs), identifying a significant influence on over
4000 genes and major cellular pathways including mitogenactivated protein kinase (MAPK).
Laponite functionality has been used in combination with several polymers to control mechanical properties of the gel [12], drug
delivery [13], cell attachment [14], and detachment [15]. Importantly, clay integration within polymer matrices provides exceptional shear-thinning modification essential for printing
applications. We have developed a functional clay-based bioink by
blending Laponite with alginate and methylcellulose in 3% w/v
concentration (3-3-3 for short) encapsulating stem cells that can
be printed with high shape fidelity and preserving cell viability for
up to 21 days in culture (Figs. 1–3).
2 Materials
2.1 Clay-Based
Biopaste
1. Sterile deionized water (DW, conductivity 18.2 MΩ cm at
20
C) (see Note 1).
64
Gianluca Cidonio et al.
colloidal suspension of clay nanoparticles, which can associate to
form gels via both repulsive and attractive interactions depending
on solid concentration and the ionic concentration of the solution
[5, 6].
Laponite has several functional properties, including (1) shear
thinning and thixotropic behavior [7], (2) retention or localization
of drugs due to strong protein-clay interactions [8], and (3) cell
stimulation [9], as well as its widespread use in polymer clay nanocomposites. Due to the physical nature of Laponite interactions,
nano-colloids and composites often display shear thinning or selfhealing properties which can be particularly useful for cell printing
processes [10].
Bioinks (biomaterials blended with living cells) have recently
come to the fore in regenerative medicine, given their versatility
and functional potential to deliver living cells in 3D, within discrete
tailored architecture and/or highly ordered cell-laden structures.
Biofabrication can generate large-scale structures with a plethora of
biomaterials. Nevertheless, bioinks that can elicit a degree of functional stimulation toward the encapsulated cells remain to be developed. Clay-based hydrogels can be tuned to retain or localize drugs
after brief exposure, stimulating angiogenesis [8] or bone formation [11] illustrating the clinical potential and opportunity
provided by Laponite and related materials to provide a one-step
procedure to encapsulate, retain, and deliver therapeutic agents
[8]. Moreover, recent advances [9] have investigated the direct
effect that Laponite nanodispersion can have on human mesenchymal stem cells (hMSCs), identifying a significant influence on over
4000 genes and major cellular pathways including mitogenactivated protein kinase (MAPK).
Laponite functionality has been used in combination with several polymers to control mechanical properties of the gel [12], drug
delivery [13], cell attachment [14], and detachment [15]. Importantly, clay integration within polymer matrices provides exceptional shear-thinning modification essential for printing
applications. We have developed a functional clay-based bioink by
blending Laponite with alginate and methylcellulose in 3% w/v
concentration (3-3-3 for short) encapsulating stem cells that can
be printed with high shape fidelity and preserving cell viability for
up to 21 days in culture (Figs. 1–3).
2 Materials
2.1 Clay-Based
Biopaste
1. Sterile deionized water (DW, conductivity 18.2 MΩ cm at
20
C) (see Note 1).
64
Gianluca Cidonio et al.