Microfluidic Study of Hydrogen Peroxide (H2O2) Transport Modeled on the MSN-DA Neuron Pathway

Reactive Oxygen Species (ROS) are produced throughout the body and can cause damage, lead to neurodegenerative disorders, and deactivate neurons involved in the release of essential neurotransmitters. However, the underlying mechanisms affecting neuronal dysfunction are controversial and are not yet well understood. Hydrogen peroxide (H2O2), a common ROS, has been shown to inhibit evoked dopamine (DA) in the Nigrostriatal region of the brain. Although unconfirmed, one theory claims that the DA-modulating H2O2 is produced in medium spiny neurons (MSN), based on close proximity. However, most literature cites H2O2 as a very small molecule which can travel far, diffuse readily, and transport easily between cells. This theory is commonly used when describing ROS damage, but more insight is needed to be able to distinguish mass transport pathways of hydrogen peroxide. The experimental setup used in this research was developed around a sensitive, cost-effective, reliable, solution for detecting H2O2. A microfluidic device was designed to simulate the basic geometry of the MSN-DA pathway and was fabricated using 3-D printing. Sample collection and colorimetric analysis was fine-tuned so that a time-dependent analysis of H2O2 transport was possible, within the limitations of the system. This work represents a proof-of-concept scenario and information gained can be used for future experiments aimed at predicting H2O2 transport within the MSN-DA pathway