PhD Dissertation: Asena Gülenay Tatar Kırtay, NOVEL CROSSLINKING APPROACH FOR 3D EMBEDDED HYBRID BIOPRINTING OF VASCULAR STRUCTURES AND ITS APPLICABILITY WITH DIFFERENT MATERIAL AND CELLS, Date & Time: 21 July, 2026 – 1:00 PM, Place: FENS L067
NOVEL CROSSLINKING APPROACH FOR 3D EMBEDDED HYBRID BIOPRINTING OF VASCULAR STRUCTURES AND ITS
APPLICABILITY WITH DIFFERENT MATERIAL AND CELLS
Asena Gülenay Tatar Kırtay
Materials Science and Nano Engineering, PhD Dissertation, July 2026
Thesis Jury
Prof. Bahattin Koç (Thesis Advisor)
Asst. Prof. Bekir Dizman
Asst. Prof. Nur Mustafaoğlu Varol
Prof. Ozan Karaman
Asst. Prof. Çiğdem Bilici
Date & Time: 21st of July, 2026 – 1:00 PM
Place: FENS L067
Zoom Link: https://sabanciuniv.zoom.us/j/
Keywords: Embedded bioprinting, extrusion bioprinting, multimaterial
bioprinting, biomaterial, blood vessel
Abstract
The fabrication of biomimetic blood vessel constructs remains a major challenge in tissue engineering due to the multilayered architecture of native vascular tissues, the need for spatially controlled cell organization, and the requirement for mechanically stable, cell-friendly material systems. Therefore, this thesis aims to develop a novel strategy for blood vessel bioprinting by integrating cell-compatible crosslinking chemistry, hybrid bioink formulation, embedded bioprinting, and rotational multimaterial bioprinting. In the first part of the thesis, a bisulfite-initiated crosslinking mechanism was developed as an alternative to conventional UV-based GelMA crosslinking to reduce potential photoinitiator- and UV-induced cellular damage. The applicability of this mechanism was further investigated using another methacrylated biomaterial, demonstrating that the approach can be extended beyond GelMA-based systems. Subsequently, a rotational multimaterial bioprinting platform was developed to overcome the limitations of sequential multimaterial deposition. The platform enables simultaneous extrusion of two different inks through a conjugated dual microcapillary nozzle while dynamically controlling material orientation during deposition. A platform-specific toolpath planning algorithm was also developed to synchronize translational and rotational movements. Finally, the developed crosslinking and printing strategies were combined for blood vessel bioprinting. A GelMA–alginate hybrid bioink was formulated to provide biological compatibility and mechanical stability, while a sodium bisulfite- and calcium chloride-containing support bath was used to crosslink both hydrogel components through complementary mechanisms. Two-layered blood vessel constructs were bioprinted using HASMC/HDF- and HASMC/HUVEC-laden bioinks to mimic the cellular organization of native vascular tissues. Overall, this thesis presents an integrated framework for fabricating multilayered, cell-laden, and perfusable vascular constructs.