Proposal Defense – Sarah Farahani

About the event

Speaker: Sarah Farahani

Group: Dr. Jeff Bell

Title: Applications of 3D Printing Towards the Fabrication of a Fully 3D-Printed Electrochemical Setup

Abstract:
The development of reliable, cost-effective, and calibration-free diagnostic tools and analytical devices for point-of-care applications has become a global, interdisciplinary effort involving materials science and analytical chemistry. This proposal aims to advance fully 3D-printed (3Dp) potentiometric sensing systems by developing, optimizing, and integrating 3Dp-ion-selective electrodes (ISEs) and solid-contact reference electrodes (SC-REs) into magnetic levitation (MagLev)-based microfluidic devices. The main hypothesis of this project is that Stereolithographic (SLA)-3Dp-methacrylate-based ion-selective membranes (the sensing element of ISEs) and optimized, novel Fused Deposition Modeling (FDM) 3Dp-ion-to-electron transducers (an inherently hydrophobic conductive filament) can be combined to create a novel fully 3Dp-potentiometric setup. This advanced biosensing technology aims to improve analytical performance, increase resistance to biofouling, enable embedding of various biomarkers or enzymes, and integrate with MagLev-assisted separation platforms. Objective 1 involves fabricating and characterizing 3Dp-ISEs for physiologically relevant electrolytes such as ammonium (NH₄⁺) and chloride (Cl⁻), using SLA and FDM 3D printing techniques to enhance reproducibility and performance. Objective 2 will develop a 3Dp-solid-contact-RE compatible with additive manufacturing for long-term monitoring and sample-independent operation. Objective 3 will engineer enzyme-based 3Dp-potentiometric (bio)sensors that convert neutral biomarkers, such as urea, into detectable ionic forms like NH₄⁺ for indirect potentiometric sensing. Objective 4 will integrate these sensors into a MagLev-assisted microfluidic platform for sample concentration, separation, and electrochemical detection using a protein- and metabolite-loaded bead model system. Additionally, a 3Dp-Zn²⁺-ISE will be developed to quantify Zn²⁺ released from metal-loaded beads and to address potential selectivity challenges in the presence of manganese (Mn²⁺) ions. Overall, this research establishes a foundational framework for fully 3D-printed potentiometric biosensors integrated with magnetic levitation, enabling scalable, multimodal diagnostic tools for decentralized, on-site (bio)sensing.