, Volume 28, Issue 3, pp 456-471,  In Vivo Methods to Study
Uptake of Nanoparticles into the Brain  368 Downloads 200
Citations 9 Comments   Several in vivo techniques have been
developed to study and measure the uptake of CNS compounds into
the brain. With these techniques, various parameters can be
determined after drug administration, including the blood-to-
brain influx constant (Kin), the permeability-surface area (PS)
product, and the brain uptake index (BUI). These techniques have
been mostly used for drugs that are expected to enter the brain
via transmembrane diffusion or by carrier-mediated transcytosis.
Drugs that have limitations in entering the brain via such
pathways have been encapsulated in nanoparticles (based on
lipids or synthetic polymers) to enhance brain uptake.
Nanoparticles are different from CNS compounds in size,
composition and uptake mechanisms. This has led to different
methods and approaches to study brain uptake in vivo. Here we
discuss the techniques generally used to measure na