Abstract

Towards Continuous Cytokine Monitoring in Organ-based Platforms

Maud Linssen, PhD Candidate, Eindhoven University of Technology

Investigations on organ-based platforms such as organoids, organ-on-a-chip, and transplantation organs, require monitoring strategies in order to optimally control the biological systems. However, there is a lack of tools to continuously measure specific low-concentration biomarkers with minimal perturbation. Biosensing by Particle Motion (BPM) is a sensing method with single-molecule resolution that has been specifically designed to enable the continuous monitoring of biomolecules at low concentrations, such as nucleic acids, metabolites, proteins and hormones. The method relies on tracking the motion of individual biofunctionalized particles (1 µm in diameter) that interact with a biofunctionalized substrate. The particles switch between bound and unbound states due to reversible single-molecule interactions, dependent on the presence of analyte molecules. Recently, sampling by microdialysis has been investigated [3]. In this paper we present the development of a BPM sensor to measure cytokines, exemplified with the detection of Interleukin-6 and TNF-a. We will present a study of molecular binders and coupling strategies, focusing on sensitivity and reversibility of the sensor. Furthermore, measurements with microdialysis will be shown. Finally, we will discuss the prospects of using BPM and microdialysis for the continuous monitoring of low-concentration biomarkers in organ-based platforms.