Caco-2 Facts

Caco-2 Permeability



The human colon carcinoma cell line caco-2 has been shown to acquire many of the features of absorptive intestinal cells when grown as a confluent monolayer.  The model mimics processes such as transcellular transport, paracellular transport, and some aspects of efflux and active transport.  Since these discoveries, the measurement of Caco-2 cell effective permeability (Peff) has emerged as a reasonable in vitro approximation of the intrinsic rate at which a drug compound passes through intestinal tissue.  Although it is a cell-based assay, and clearly higher throughput than animal studies, the generation of high quality Caco-2 Peff  data is still a fairly expensive process, and medium throughput at best.  

The assay was designed to measure directional Caco-2 permeability of test compounds. 

A diverse collection of marketed drugs, drug failures and non-drugs was assembled from a broad variety of  structural and target classes.  The compounds also include a range of absorption and transport properties.


List of Compounds

A partial list of compounds in this dataset can be found here.  Additional compounds are non-drug library compounds of unique structures.



Effective permeability (Peff) was measured in the apical -> basolateral (A/B) direction in 20-23 day old caco-2 cell cultures (Passage number 30-45) grown on a 0.31cm2 filter.  The donor side of the chamber was dosed at a concentration of 100 uM in 300 ul of Ringers buffer at pH 7.4 containing a final concentration of 1.0% DMSO.  The receiver side of the chamber contained 1200 ul of an identical buffer.  Samples were incubated at 37 C, in a 95% humidity chamber containing 5% CO2.  


100 ul samples from the receiver side of the chamber were taken at 30, 50, 70, and 90 minutes post experiment initiation.  Four replicates of each sample were performed on each day.  Bioanalysis was performed using LC-MS, HLPC-UV or LSC.  Peff was calculated using the following formula:


Peff (cm/sec) = (dX/dt)/(A*Co*60)

where X =  mass transported, A = surface area and Co = initial donor drug concentration

Compound Diversity

For a series of plots to show the diversity of the Caco-2 training set compounds click here


Raw data

Each data set is accompanied by the raw data collected during the assays. Click here for an example raw data file


Reference Material

 Check the downloads page for additional reference material