Fabrication of Microtube-Embedded Chip to Mimic Blood-Brain Barrier Capillary Vessels

Capillary vessels of the blood-brain barrier (BBB) regulate the transportation of solutes into the brain and provide defense against the disease-causing pathogens and neurotoxins present in the blood. Paradoxically, this regulation also prevents drug transportation into the brain. These unique characteristics of the BBB cause impediment in the treatment of neurological diseases. The development of preclinical models that mimic the BBB capillary vessel is crucial to investigate the complex transport mechanism. Microfluidics-based in vitro models are now extensively investigated for therapeutic applications due to the ability to create a tunable dynamic extracellular microenvironment. One of the main challenges of creating a BBB-on-a-chip is to recapitulate the tubular capillary structure. This chapter presents two novel fabrication methods for microfluidic devices embedded with tubular micro-channels that resemble the diameter and morphology of capillary vessels. These microfluidic devices can be seeded with cells for physiological and pathological studies to support future drug development.