Electrically conductive nanofibrous scaffold composed of poly(ethylene glycol)-modified polypyrrole and poly(ε-caprolactone) for tissue engineering applications

Chan

Biotech & Bioengineering

et al. 2021

The application of scaffold-based stem cell transplantation to enhance peripheral nerve regeneration has great potential. Recently, the neuroregenerative potential of tacrolimus (a U.S. Food and Drug Administration-approved immunosuppressant) has been explored. In this study, a fibrin gel-based drug delivery system for sustained and localized tacrolimus release was combined with rat adipose-derived mesenchymal stem cells (MSC) to investigate cell viability in vitro. Tacrolimus was encapsulated in poly(lactic-co-glycolic) acid (PLGA) microspheres and suspended in fibrin hydrogel, using concentrations of 0.01 and 100 ng/ml. Drug release over time was measured. MSCs were cultured in drug-released media collected at various days to mimic systemic exposure. MSCs were combined with (i) hydrogel only, (ii) empty PLGA microspheres in the hydrogel, (iii) 0.01, and (iv) 100 ng/ml of tacrolimus PLGA microspheres in the hydrogel. Stem cell presence and viability were evaluated. A sustained release of 100 ng/ml tacrolimus microspheres was observed for up to 35 days. Stem cell presence was confirmed and cell viability was observed up to 7 days, with no significant differences between groups. This study suggests that combined delivery of 100 ng/ml tacrolimus and MSCs in fibrin hydrogel does not result in cytotoxic effects and could be used to enhance peripheral nerve regeneration.

Section: Discussionmentioning

confidence: 99%

Combined local delivery of tacrolimus and stem cells in hydrogel for enhancing peripheral nerve regeneration

Chan

Biotech & Bioengineering

et al. 2021

Applied Materials Today

“…The study by [145] provides an in-depth analysis of the various physical characteristics of biocompatible polymers used for the creation of scaffolds in tissue engineering. SMPs fabricated into ultrafine nanoscale fibers have been used to produce tissue engineering scaffolds [146,147], as shown in Fig. 21.…”

Section: Regenerative Medicines and Tissue Engineeringmentioning

confidence: 99%

4D printing of materials for the future: Opportunities and challenges

Joshi

Rawat

Karunakaran

et al. 2020

145

The concept of 4D printing involves the formation of complex three-dimensional structures having the ability to adopt different shapes and forms when subjected to different environmental stimuli. Some researchers simply view this technique as an extension of 3D printing or additive manufacturing with the added constraint of time. However, the unique shape change mechanism exhibited in this process is due to a combination of shape programming and the usage of smart active materials mostly polymers. This review article highlights the various smart materials, activation mechanisms and the shape-changing techniques employed in the 4D printing process. The potential of these shape-changing structures and their current applications in various biomedical and engineering fields is also explored. The article aims to emphasize the potential and viability of 4D printing and is directed towards providing an in-depth insight into the 4D printing process.

“…Chemical oxidation polymerization approach is one of the strategies used in scaffold fabrication. Massoumi et al used this method to produce PEGs-b-(PPy)4 from PyPEGs macromonomers obtained from Steglich esterification of PEGs(OH)4 using pyrrole-2-carboxylic acid [ 172 ]. Solution of the electrospun-synthesized PEGs-b-(PPy)4 copolymer and PCL to produce nanofibrous scaffolds.…”

Section: Specific Improvement Strategies For Specific Body Partsmentioning

confidence: 99%

Conductive Polymeric-Based Electroactive Scaffolds for Tissue Engineering Applications: Current Progress and Challenges from Biomaterials and Manufacturing Perspectives

Marsudi

Ariski

Wibowo

et al. 2021

IJMS

The practice of combining external stimulation therapy alongside stimuli-responsive bio-scaffolds has shown massive potential for tissue engineering applications. One promising example is the combination of electrical stimulation (ES) and electroactive scaffolds because ES could enhance cell adhesion and proliferation as well as modulating cellular specialization. Even though electroactive scaffolds have the potential to revolutionize the field of tissue engineering due to their ability to distribute ES directly to the target tissues, the development of effective electroactive scaffolds with specific properties remains a major issue in their practical uses. Conductive polymers (CPs) offer ease of modification that allows for tailoring the scaffold’s various properties, making them an attractive option for conductive component in electroactive scaffolds. This review provides an up-to-date narrative of the progress of CPs-based electroactive scaffolds and the challenge of their use in various tissue engineering applications from biomaterials perspectives. The general issues with CP-based scaffolds relevant to its application as electroactive scaffolds were discussed, followed by a more specific discussion in their applications for specific tissues, including bone, nerve, skin, skeletal muscle and cardiac muscle scaffolds. Furthermore, this review also highlighted the importance of the manufacturing process relative to the scaffold’s performance, with particular emphasis on additive manufacturing, and various strategies to overcome the CPs’ limitations in the development of electroactive scaffolds.