Biodegradable photocrosslinkable poly(depsipeptide‐co‐ε‐caprolactone) for tissue engineering: Synthesis, characterization, and In vitro evaluation

Abstract

Stereolithography has become increasingly popular in scaffold fabrication due to automation and well-controlled geometry complexity, and consequently, there is a great need for new suitable biodegradable photocrosslinkable polymers. In this study, a new type of photocrosslinkable poly(ester amide) was synthesized based on e-caprolactone and L-alaninederived depsipeptide and was applied to fabrication of threedimensional (3D) scaffolds by stereolithography. 1 H nuclear magnetic resonance and Fourier transform infra-red analysis confirmed the formation of new bonds during the polymer synthesis. Incorporation of depsipeptide increased the glass transition temperature and hydrophilicity of the polymer and accelerated hydrolytic degradation compared with the poly(ecaprolactone) homopolymer. The compressive strength of the 3D scaffolds increased with the increasing depsipeptide content. This work demonstrated that incorporation of depsipeptide into photocrosslinkable polyesters resulted in excellent cytocompatibility and tunable degradation rates and mechanical properties and thus expanded the repertoire of biomaterials suitable for 3D photofabrication of high-resolution tissue engineering scaffolds.

Synthesis of Well‐Defined Dihydroxy Telechelics by (Co)polymerization of Morpholine‐2,5‐Diones Catalyzed by Sn(IV) Alkoxide

“…Thus, telechelic oDPs show great promise as building blocks for biomedical applications. [1][2][3][4][5][6][7] Especially amorphous, solely depsipeptide-based, telechelics are interesting candidate materials for tissue engineering and drug delivery applications. [5,[8][9][10][11][12][13][14][15] Similar to telechelics based on polyesters, well-defined telechelic oDPs are the prerequisite when these oDPs should be used as functional building blocks for follow-up reactions like multiblock copoly mer synthesis by polyaddition reactions.…”

“…[9] Tin(II) 2-ethylhexanoate (Sn(Oct) 2 ) is the most commonly used catalyst for the polymerization of MDs as well as their copolymerization with other cyclic monomers, that is, lactide and ε-caprolactone. [7,[20][21][22] However, ROP catalyzed by Sn(Oct) 2 still encounters the challenge of poor reaction control of the polymer molecular weight, as well as loss of terminal groups caused by the side reactions resulting from any hydroxyl-containing species and by transesterification reactions (typical inter-and intramolecular reaction and backbiting transesterification and/or chain transfer reactions). [23] Impurities, that is, water and organic acids are diffluent in Telechelics Well-defined dihydroxy telechelic oligodepsipeptides (oDPs), which have a high application potential as building blocks for scaffold materials for tissue engineering applications or particulate carrier systems for drug delivery applications are synthesized by ring-opening polymerization (ROP) of morpholine-2,5-diones (MDs) catalyzed by 1,1,6,6-tetra-n-butyl-1,6-distanna-2,5,7,10-tetraoxacyclodecane (Sn(IV) alkoxide).…”

Preparation of Designed Poly(trimethylene carbonate) Meniscus Implants by Stereolithography: Challenges in Stereolithography

“…[7][8][9] In many biomedical applications like tissue engineering, biodegradable scaffolds are desired. Biodegradable functionalized oligomers (or macromers) that have been developed for these purposes have been based on ε-caprolactone, [4,10] trimethylene carbonate, [5,11] and d,l-lactide. [3,12] Also poly(propylene fumerate) materials [1,13,14] have been investigated.…”

Three-dimensional fabrication of cell-laden biodegradable poly(ethylene glycol-co-depsipeptide) hydrogels by visible light stereolithography

“…In our previous study, 21 we synthesized a biodegradable photocrosslinkable poly(ε-caprolactone- co -depsipeptide) for use in DLP-based SLA to fabricate porous hydrophobic TE scaffolds. Previously, depsipeptides have been used to synthesize hydrophilic PEG-based copolymers for use as non-photocrosslinkable, temperature responsive gels and drug delivery micelles.…”