Tuning the three-dimensional architecture of supercritical CO2 foamed PCL scaffolds by a novel mould patterning approach

Engineering bioactive synthetic polymers for biomedical applications: a review with emphasis on tissue engineering and controlled release

“…134,135 The lack of any requirement for cytotoxic solvents, the possibility of operating at mild conditions (for example, with PCL, at temperatures below 37 1C), and the potential to process a wide variety of polymers for biomedical use are the main advantages of the technique. 136 The use of CO 2 or N 2 as a blowing agent represents another important advantage of supercritical foaming in tissue engineering applications, since these gases rapidly leave the porous matrix during foaming and have negligible residual cytotoxicity. 132 The combined use of different technologies allows for the production of advanced structures in terms of multi-scale porosity, hierarchical structures, functionalization, and graded systems.…”

“…139 Salerno et al combined microfabrication and gas foaming to achieve dualshaped porous PCL scaffolds with pre-defined arrays of microchannels within a foamed porosity that mimicked the structure of tissues like bone, blood vessels, and nerve tissues. 136 Gas foaming methods can be easily utilized with SyP-based composites without extensive modification of the processing conditions typically suitable for the neat SyPs. A wide variety of additives are now being utilized to improve foamability and foaming control or to improve the functional and structural properties of the scaffold.…”

“…In the following sections, we will discuss the current literature that describes the functionalization of SyPs to impart antimicrobial, actuation, and conductive properties. From left to right: 3D printing (adapted from Zhou et al 139 with permission from Elsevier), solvent casting/particulate leaching (SC/PL) (adapted from Mao et al 172 with permission from Elsevier), thermally induced phase separation (TIPS) (adapted from Gay et al 173 with permission from Elsevier), foaming (adapted from Salerno et al 174 with permission from Elsevier) and electrospinning (adapted from Xue et al 102 with permission from the American Chemical Society). Circle size (SEM images and pink circles) is proportional to the number of Google Scholar results from 2015 (access January 26, 2020).…”

Advances in Biodegradable 3D Printed Scaffolds with Carbon-Based Nanomaterials for Bone Regeneration

“…To have the appropriate pore size distribution and interconnectivity, different approaches to fabricate porous scaffolds have been studied: salt-leaching [ 203 , 204 , 205 ], gas foaming [ 206 , 207 ], electrospinning [ 208 , 209 , 210 ] and freeze-drying [ 211 , 212 ]. However, with these fabrication methods, it is possible to produce bone tissue-engineered scaffolds without controlling pore size distribution and shape, porosity and interconnectivity.…”

Modeling of Two‐Step Supercritical CO2 Foaming to Fabricate Poly(ε‐caprolactone) Scaffolds

“…These kinds of scaffolds can be manufactured using supercritical foaming (SCF) with a two‐step depressurization rate. SCF is a very attractive method for scaffold fabrication because it operates at low temperature without any chemical solvent, and it is a highly controllable technique 6–8. In a typical SCF experiment with a two‐step depressurization rate, a stainless‐steal bed is charged with the solid polymer, and its pressure increases by injecting a high‐pressure CO 2 flow until achieving the desired pressure and temperature.…”