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Fabrication of complex structures usually requires a combination of different advanced manufacturing techniques at different length scales. In this work, we discuss the structure‐properties relationship of recently developed biodegradable poly(butylene succinate‐dilinoleic succinate) (PBS‐DLS) copolymers modified with hydrophilic poly(ethylene glycol) (PEG) towards their processibility via 3D printing and electrospinning. Notably, filaments suitable for 3D printing with 1.75 mm diameter were fabricated directly from the reactor after the synthesis of copolymers through extruding polymer melt into a water bath thus overcoming the postprocessing. Two series of copolymers containing 60 wt% and 70 wt% of hard PBS content were synthesized using magnesium‐titanium butoxide as heterometallic catalyst. Differential scanning calorimetry indicated biphasic morphology with low‐glass transition temperature and high‐melting point, which were dependent from the PBS hard segments content. Crystallized copolymers exhibited distinct spherulitic morphology, but presence of crystallites has no adverse effect on warping or delamination of subsequent layers during 3D printing. Furthermore, these copolymers demonstrated also easy processability through electrospinning, yielding uniform nanofibers with diameters ranging from 400 to 600 nm. The addition of 5 wt% PEG to copolymers with higher hard segments content (70 wt%) increased the elasticity up to 830% and improved hydrophilicity of the copolymers. Overall, these findings together with the excellent cell viability of new materials highlight their potential for different applications, including the biomedical sector. [ABSTRACT FROM AUTHOR]

Appropriate selection of suitable materials and methods is essential for scaffolds fabrication in tissue engineering. The major challenge is to mimic the structure and functions of the extracellular matrix (ECM) of the native tissues. In this study, an optimized 3D structure containing poly(3-hydroxybutyrate) (P3HB), multiwalled carbon nanotubes (MCNTs) and curcumin (CUR) was created by electrospinning a novel biomimetic scaffold. CUR, a natural anti-inflammatory compound, has been selected as a bioactive component to increase the biocompatibility and reduce the potential inflammatory reaction of electrospun scaffolds. The presence of CUR in electrospun scaffolds was confirmed by 1H NMR and Fourier-transform infrared spectroscopy (FTIR). Scanning electron microscopy (SEM) revealed highly interconnected porosity of the obtained 3D structures. Addition of up to 20 wt% CUR has enhanced mechanical properties of the scaffolds. CUR has also promoted in vitro bioactivity and hydrolytic degradation of the electrospun nanofibers. The developed P3HB-MCNT composite scaffolds containing 20 wt% of CUR revealed excellent in vitro cytocompatibility using mesenchymal stem cells and in vivo biocompatibility in rat animal model study. Importantly, the reduced inflammatory reaction in the rat model after 8 weeks of implantation has also been observed for scaffolds modified with CUR. Overall, newly developed P3HB-MCNTs-CUR electrospun scaffolds have demonstrated their high potential for tissue engineering applications. [ABSTRACT FROM AUTHOR]

Biodegradable polymers are an active area of investigation, particularly ones that can be produced from sustainable, biobased monomers, such as copolymers of poly(butylene succinate) (PBS). In this study, we examine the enzymatic degradation of poly(butylene succinate-dilinoleic succinate) (PBS-DLS) copolymers obtained by “green” enzymatic synthesis using lipase B from Candida antarctica (CALB). The copolymers differed in their hard to soft segments ratio, from 70:30 to 50:50 wt %. Enzymatic degradation was carried out on electrospun membranes (scaffolds) and compression-moulded films using lipase from Pseudomomas cepacia. Poly(ε-caprolactone) (PCL) was used as a reference aliphatic polyester. The degradation process was monitored gravimetrically via water uptake and mass loss. After 24 days, approx. 40% mass loss was observed for fibrous materials prepared from the PBS-DLS 70:30 copolymer, as compared to approx. 10% mass loss for PBS-DLS 50:50. Infrared spectroscopy (FTIR) and size exclusion chromatography (SEC) analysis were used to examine changes in chemical structure. Differential scanning calorimetry (DSC) and scanning light microscopy (LSM) revealed changes in degree of crystallinity, and changes in surface morphology, consistent with a surface erosion mechanism. We conclude that the obtained copolymers are suitable for tissue engineering applications thanks to tuneable degradation and lack of acidification during breakdown. [ABSTRACT FROM AUTHOR]

A new copolymer poly(butylene succinate-dilinoleic succinate) (PBS-DLS) has been successfully synthesized and its suitability for the fabrication of electrospun fiber mats has been investigated for the obtaining both electrospun scaffolds of neat PBS-DLS and also in blend with poly(glycerol sebacate) (PGS). After optimizing the electrospinning process for both neat and PGS/PBS-DLS (ratio 1:2) blend materials, homogeneous fiber mats have been obtained with an average fiber diameter of 2.5 ± 0.5 μm and 2.0 ± 0.2 μm, for neat and blend mats, respectively. Mechanical properties and degradation behavior in PBS were investigated to evaluate their suitability for soft tissue engineering applications. A feasibility study of the obtained electrospun mats functionalization was performed and positive results were obtained, demonstrating the versatility and suitability of PGS/PBS-DLS electrospun fibers as candidate for soft tissue engineering applications. [ABSTRACT FROM AUTHOR]

Electrospinning is one of the most investigated methods used to produce polymeric fiber scaffolds that mimic the morphology of native extracellular matrix. These structures have been extensively studied in the context of scaffolds for tissue regeneration. However, the compactness of materials obtained by traditional electrospinning, collected as two-dimensional non-woven scaffolds, can limit cell infiltration and tissue ingrowth. In addition, for applications in smooth muscle tissue engineering, highly elastic scaffolds capable of withstanding cyclic mechanical strains without suffering significant permanent deformations are preferred. In order to address these challenges, we report the fabrication of microscale 3D helically coiled scaffolds (referred as 3D-HCS) by wet-electrospinning method, a modification of the traditional electrospinning process in which a coagulation bath (non-solvent system for the electrospun material) is used as the collector. The present study, for the first time, successfully demonstrates the feasibility of using this method to produce various architectures of 3D helically coiled scaffolds (HCS) from segmented copolyester of poly (butylene succinate- co -dilinoleic succinate) (PBS-DLS), a thermoplastic elastomer. We examined the role of process parameters and propose a mechanism for the HCS formation. Fabricated 3D-HCS showed high specific surface area, high porosity, and good elasticity. Further, the marked increase in cell proliferation on 3D-HCS confirmed the suitability of these materials as scaffolds for soft tissue engineering. Unlabelled Image • Bath collector enables electrospinning of 3D helically coiled scaffolds (HCS) • Various architectures can be obtained by tuning process parameters • Copolyester HCS showed high specific surface area and porosity, good elasticity • HCS had marked increase in cell proliferation vs. conventional 2D scaffolds [ABSTRACT FROM AUTHOR]

Electrospun fibers based on combinations of poly(ε-caprolactone) (PCL) and poly(glycerol sebacate) (PGS) have been studied for applications in cardiac tissue engineering. The aim of the present study is to demonstrate the fabrication of PCL and PGS prepolymer or mildly crosslinked PGS by electrospinning using less toxic solvents, like acetic acid, as opposed to conventional solvents such as chloroform or dichloromethane. The morphological and physiochemical properties and degradation susceptibility of the fiber mats were determined. A cell study using ST2 cells was performed to assess cytocompatibility. Neat PCL and PCL/PGS blends showed defect-free microstructures, whereby the average fiber diameter increased with the addition of PGS (0.8 ± 0.3 μm and 1.3 ± 0.7 μm, respectively). The mechanical properties were tested at 23 °C and 37 °C and showed higher values compared to native human myocardium. Degradation studies revealed a fast PGS degradation but the mildly cross-linked PGS resulted in acidification of the degradation medium. The biocompatibility was significantly increased when the samples were disinfected in 70% v/v ethanol in comparison to ultra-violet light disinfection. PCL/PGS fibers fabricated with acetic acid proved to be potentially suitable for application in cardiac tissue engineering based on their mechanical properties and biodegradability. Unlabelled Image • Benign electrospinning of poly(ε-caprolactone)(PCL)/poly(glycerol sebacate)(PGS) • Homogenous and defect-free PCL/PGS fiber mats were achieved using acetic acid. • PGS increased the degradation process in the blend fiber mats. • Ethanol disinfection improved cell viability of blend compared to ultraviolet light. [ABSTRACT FROM AUTHOR]