Microfluidic interfaces for chronic bidirectional access to the brain.

Here, we used micron-scale 3D printing to develop microfluidic interfaces which provide chronic fluidic access to the brain of preclinical research models. In mice, we show the delivery interface enables faster, more precise and physiologically less disruptive fluid injection. Moreover, we demonstrate the blood brain barrier (BBB) is intact after chronic implantation of the sampling interface and establish frequent, longitudinal sampling of CSF and biomarkers from the ventricle over long time periods of up to 200 days. ### Competing Interest Statement The authors have declared no competing interest.