Traumatic brain injury biomarker discovery using mass spectrometry imaging of 3D neural cultures

Abstract

Biomarker research is of great interest in the field of traumatic brain injury (TBI), since there are numerous potential markers that may indicate central nervous system damage, yet the brain is normally well isolated and discovery is at its infancy. Traditional methods for biomarker discovery include time consuming multi step chromatographic mass spectrometery (MS) techniques or pre-defined serial probing using traditional assays, making the identification of biomarker panels limiting and expensive. These shortfalls have motivated the development of a MS based probe that can be embedded into 3D neural cultures and obtain temporal and spatial information about the release of biomarkers. Using the high sensitivity MS ionization method of nano-electrospray ionization (nano-ESI) with an in-line microdialysis (MD) unit allows us to use MS to analyze low concentrations of TBI biomarkers from within cell cultures with no need for off-line sample manipulation. This thesis goes through the development of the probe by studying the theoretical principles, simulations and experimental results of the probe's capability to sample small local concentrations of a marker within cell culture matrix, the MD unit's sample manipulation capabilities, and the ability to detect markers using in-line MD-nano-ESI MS.