Process Development and Characterization of Bio-Inks for SLA and Inkjet Printing Applications

Abstract

This thesis investigates the design, fabrication, and evaluation of biocompatible and functional structures using additive manufacturing techniques tailored for biomedical applications. The research centers around two complementary approaches: stereolithography (SLA) for printing of microfluidic devices and tissue scaffolds, and inkjet printing using a custom-built robotic system with dual printheads for multi-material deposition on both flat and curved surfaces. A major innovation lies in combining biocompatible polymer and conductive inks to create hybrid constructs capable of supporting cell culture and embedding simple electronics. SLA printing enables the creation of complex architectures such as integrated microfluidic channels and porous scaffolds. For dynamic and multi-material applications, inkjet printing was used to deposit silver-based conductive inks and insulating biomaterials. To address the challenge of printing on irregular geometries, we incorporated a 3D scanning system into the workflow and used a python script for surface mapping and path planning. This allowed the robotic arm to accurately print conformal patterns on different 3D objects. Critical to this process was the real-time monitoring and calibration of droplet formation using a drop-watching camera system. UV and NIR curing modules were integrated into the robotic system to enable on-the-fly crosslinking and sintering, reducing fabrication time and improving mechanical stability. To validate the functionality of the printed constructs, we conducted mechanical testing, electrical measurements, and basic cell viability assessments for SLA-printed microfluidic channels seeded with cells. This research demonstrates a scalable, multi-material additive manufacturing workflow for producing smart biomedical devices, patient-specific implants with integrated sensors, and drug delivery platforms. The work paves the way for further development of in situ printing technologies, dielectric biomaterials for capacitive sensing, and hybrid devices that merge tissue engineering with bioelectronics.

Date of Award	2025
Original language	English
Supervisor	Jaroslaw Jacak (Supervisor)