Localized and Automated Chemical and Oxygen Delivery System for Microfluidic Brain Slice Devices

To better study in vitro models of the brain, a localized delivery system is necessary due to the region specific functionality of the brain. The proposed system allows drugs and oxygen of controllable concentrations to be delivered. The delivery system is integrated into a polydimethylsiloxane microfluidic brain slice device and uses valves controlled by the LabVIEW programming language. Delivery is controlled by adjusting the opening/closing frequencies of the valves. Fluorescein isothiocyanate, a fluorescent dye, was used to characterize the delivery with and without brain tissue (~300 μm). A linear relationship was found correlating the valve frequencies and the intensity showing how easily controlled concentrations can be delivered. A delivery system to automatically mix and deliver oxygen concentrations between 0% and 21% was developed. Accurate and precise outputs were obtained. Combined, these two delivery systems will allow controllable drug and oxygen concentrations to be tested at defined regions of the brain.