Dear Viviana,

For in vitro models of the BBB, please see the following links which contain contact addresses of companies making such service:

1-For this need Across Barriers has established and standardized an in vitro model of the blood-brain-barrier which is based on cerebral capillary endothelial cells.

http://www.acrossbarriers.de/en/services/in-vitro-pharmacokinetics/blood-brain-barrier/

2-Flocel’s in vitro BBB Model

http://www.flocel.com/

3-PAMPA

Blood-Brain Barrier Permeability CNS Screening of candidate drug molecules is done using a PAMPA assay to model blood-brain barrier (BBB) permeability. Rodent in vivo and in situ studies of the kinetics of drug uptake across the BBB are valuable tools for assessing factors important to steady-state brain penetration. These are relatively expensive and time consuming assays to do, and are done only sparingly. Animal studies can be augmented by PAMPA, which for BBB uses a mixture of phospholipids infused into lipophilic microfilters, with net negative lipid charge, a system mimicking many of the properties of brain lipid membranes. The data is used to predict brain uptake kinetics, as indicated by PS values determined by in situ perfusion methods

http://www.pion-inc.com/Products/Permeability

Hoping this will be helpful,

Rafik

Hello, there is a relatively simple HPLC method available, which is described in: 

Nanoscale Res Lett. 2014 Dec;9(1):2406. doi: 10.1186/1556-276X-9-684. Epub 2014 Dec 18.

Enhancing oral bioavailability of quercetin using novel soluplus polymeric micelles.

Dian L1, Yu E, Chen X, Wen X, Zhang Z, Qin L, Wang Q, Li G, Wu C.

Dear Viviana, Have you solved your quercetin analysis?

If not, please contact me, I can help, lots of greetings, Brig