Scopus İndeksli Yayınlar Koleksiyonu / Scopus Indexed Publications Collection
Permanent URI for this collectionhttps://hdl.handle.net/11147/7148
Browse
2 results
Search Results
Article Synthetic Memory: A Key Link Between Biocatalytically Synthesized Polyesters and Melt Electrowriting Performance(Taylor & Francis inc, 2025) Dinckal, Sanem; Yildiz, Umit HakanThe biocatalytic synthesis of polycaprolactone (PCL) and its copolymers has garnered significant attention due to their reduced toxicity and enhanced 3D processability compared to metal-catalyzed alternatives. The objective of this study is to employ biocatalysts-citric acid (CA), glycolic acid (GA) and salicylic acid (SAA)-and explore their catalytic effects on the synthesis of poly(epsilon-caprolactone) (PCL) and poly(epsilon-caprolactone)-b-poly(delta-valerolactone) (PCL-b-PVL) block copolymers. Additionally, we aimed to examine the link between synthetic memory of resultant PCL and PCL-b-PVL polymers and their melt electrowriting performance. Nuclear magnetic resonance analysis confirms successful synthesis of copolymers by monitoring signals of hydrogens at 2.30 ppm. Differential scanning calorimetry results reveal shifts in thermal properties of copolymers upon varying biocatalysts CA-, SAA- and GA-catalyzed copolymers exhibit Tm values between similar to 52 and 54 degrees C. Melt electrowriting (MEW) results demonstrate that catalyst selection plays significant role in fiber morphology and scaffold architecture, with GA- and CA-catalyzed copolymers exhibiting finer fibers (5-8 mu m), while SAA led to thicker fibers (similar to 12 mu m) and reduced spacing. Moreover, precipitation solvents MeOH and acetonitrile (ACN) affect fidelity, with ACN-prepared scaffolds exhibiting more uniform fiber diameters. Atomic force microscopy imaging of electrowritten scaffolds made of ACN- and MeOH-precipitated PCL-b-PVL both exhibit large (>15 mu m) and smaller (<10 mu m) spherulitic structure as major topological features. These findings confirm that the synthetic memory of polyesters-governed by catalyst choice and processing conditions-directly influences their printability, making them promising candidates for MEW-based biomedical scaffolds in tissue engineering, where fine fiber morphology and architectural fidelity are essential for cell attachment and tissue regeneration.Article Citation - WoS: 5Citation - Scopus: 6Fabrication of Gelatin-Polyester Based Biocomposite Scaffold Via One-Step Functionalization of Melt Electrowritten Polymer Blends in Aqueous Phase(Elsevier B.V., 2024) Köksal,B.; Kartal,R.B.; Günay,U.S.; Durmaz,H.; Yildiz,A.A.; Yildiz,Ü.H.The rapid manufacturing of biocomposite scaffold made of saturated-Poly(ε-caprolactone) (PCL) and unsaturated Polyester (PE) blends with gelatin and modified gelatin (NCO-Gel) is demonstrated. Polyester blend-based scaffold are fabricated with and without applying potential in the melt electrowriting system. Notably, the applied potential induces phase separation between PCL and PE and drives the formation of PE rich spots at the interface of electrowritten fibers. The objective of the current study is to control the phase separation between saturated and unsaturated polyesters occurring in the melt electro-writing process and utilization of this phenomenon to improve efficiency of biofunctionalization at the interface of scaffold via Aza-Michael addition reaction. Electron-deficient triple bonds of PE spots on the fibers exhibit good potential for the biofunctionalization via the aza-Michael addition reaction. PE spots are found to be pronounced in which blend compositions are PCL-PE as 90:10 and 75:25 %. The biofunctionalization of scaffold is monitored through C[sbnd]N bond formation appeared at 400 eV via X-ray photoelectron spectroscopy (XPS) and XPS chemical mapping. The described biofunctionalization methodology suggest avoiding use of multi-step chemical modification on additive manufacturing products and thereby rapid prototyping of functional polymer blend based scaffolds with enhanced biocompatibility and preserved mechanical properties. Additionally one-step additive manufacturing method eliminates side effects of toxic solvents and long modification steps during scaffold fabrication. © 2024 Elsevier B.V.