Development of microfluidic bubble perfusion device for neuropeptide analysis from ex vivo brain slice models

Characterized by social impairments, repetitive or compulsive behaviors, and speech deficits, the underlying causes of Autism Spectrum Disorder (ASD) are currently unknown. Both oxytocin and arginine vasopressin are involved in regulating social behaviors in mammals and the dysregulation of each is thought to play a role in social impairments associated with ASD. Studying the secretion dynamics of these peptides can help us better understand regulatory relationships that may be involved in neurodevelopmental disorders like ASD. Microfluidic brain slice culture is an important tool for ex vivo modeling of basal and diseased state neurochemistry. A significant challenge to culturing brain slices in microfluidic flow systems is the efficient delivery of oxygen to enable medium to long-term viability of tissue slice. A microfluidic slice culture device that delivers continuous flow of carbogen gas-segmented culture media droplets to an immobilized brain tissue slice for total perfusion, enabling efficient oxygenation has been developed. The size of tissue slices, and the dimensions of the required tissue chamber present a lower limit of droplet volume on the order of 10 μL, which is a relatively large volume compared to many microfluidic systems. For downstream assay of cellular secretions, sample preconcentration is needed. An electrophoretic platform for sample preconcentration within the gas-segmented perfusate droplets has been developed.