Levofloxacin-loaded star poly(ε-caprolactone) scaffolds by additive manufacturing

Abstract

The employment of a tissue engineering scaffold able to release an antimicrobial agent with a controlled kinetics represents an effective tool for the treatment of infected tissue defects as well as for the prevention of scaffolds implantation-related infectious complications. This research activity was aimed at the development of additively manufactured star poly(ε-caprolactone) (*PCL) scaffolds loaded with levofloxacin, investigated as antimicrobial fluoroquinolone model. For this purpose a computer-aided wet-spinning technique allowing functionalizing the scaffold during the fabrication process was explored. Scaffolds with customized composition, microstructure and anatomical external shape were developed by optimizing the processing parameters. Morphological, thermal and mechanical characterization showed that drug loading did not compromise the fabrication process and the final performance of the scaffolds. The developed *PCL scaffolds showed a sustained in vitro release of the loaded antibiotic for 5 weeks. The proposed computer-aided wet-spinning technique appears well suited for the fabrication of anatomical scaffolds endowed with levofloxacin-releasing properties to be tested in vivo for the regeneration of long bone critical size defects in a rabbit model.

Integrated three‐dimensional fiber/hydrogel biphasic scaffolds for periodontal bone tissue engineering

“…This result is consistent with those of recent studies showing that in the wet-spinning process the non-solvent-induced coagulation generally leads to high levels of polymer crystallinity. 36,54 No statistically significant differences were observed when comparing data sets from the second heating scan of raw PCL, PCL 1 scaffolds and PCL/HA 1 scaffolds, in agreement with what was found during TGA analysis, suggesting that the employed materials processing technique did not cause remarkable chemical-physical changes in polymer structure. T m and crystallinity obtained from the endothermic peaks of biphasic scaffold traces are statistically comparable to those of PCL 1 scaffolds.…”

Potential core–shell designed scaffolds with a gelatin‐based shell in achieving controllable release rates of proteins for tissue engineering approaches

“…The GT‐based scaffolds without cross‐linking with higher GT amount demonstrated an intense initial bursts specially in the first hour due to the dissolution of GT part in PBS medium (as confirmed by biodegradation profiles). Many biological agents need different rates of administration or for some others, high initial rate in the first hours or a rapid release is needed to provide a quick relief and exert a strong therapeutic effect . As the initial burst release is often considered a negative consequence, it is needed to avoid the burst release because it may result in the concentration above toxic level in vivo .…”

Additive Manufacturing of Poly(Methyl Methacrylate) Biomedical Implants with Dual‐Scale Porosity

“…In general, the compressive stress–strain curves were characterized by an initial linear region followed by a plateau and a subsequent area of increasing stress up to a maximum value before sample breaking ( Figure a). As hypothesized in previous articles on biodegradable polymeric scaffolds by CAWS,[12d,14] the initial linear region could be attributed to a response of the fiber–fiber contact areas to the applied deformation, the plateau area to the subsequent collapse of the porous network, and the continuous stress increase in the third region to a densification of the polymeric structure that behaves like a dense matrix. As summarized in Table 3 , PMMA‐Dry samples showed the highest compressive modulus while PMMA‐EtOH samples had the highest compressive strength, highlighting the influence of differences in macro‐ and microstructural features observed by SEM analysis on the resulting mechanical performance.…”

“…They found that by increasing material porosity it was possible to suit its rigidity to that of osteoporotic cancellous bone in order to prevent mechanical mismatch‐related problems, such as bone fracture and cement leakage, often clinically observed as the result of stress‐shielding effects. In comparison to scaffolds made of biodegradable polyesters (i.e., PCL, *PCL, and PHBHHx) with a similar layered fibrous structure prepared by CAWS,[12a,b,d,14] the developed implants showed much higher compressive and tensile modulus mainly as a consequence of the higher rigidity of PMMA.…”

“…The developed materials engineering strategy provides powerful tools for developing sophisticated polymeric architectures aimed at tailoring implant bioactive properties, including tissue integration and controlled release of loaded drugs . Indeed, the possibility of directly loading the implant with a bioactive agent by processing a polymeric solution containing it as solute or suspension, opens new possibilities for the development of novel bioactive PMMA implants. The industrial translation of production processes based on the reported AM strategy will rely on the use of solvents allowed in medical devices manufacturing that are completely removed from the implant during the fabrication and postprocessing treatment.…”