Figure 1: Log P<sub>e</sub> can be calculated from the equation as reported by Faller et al. (1)

Figure 1.Log Pe can be calculated from the equation as reported by Faller et al. (1)

Table 1Description of variables used to calculate Log Pe

Note 1: For consistent and optimal performance, it is important to allow for complete evaporation of hexane. Once evaporation is complete the hexadecane membrane is stable for weeks.

Note 2: To ensure the hexadecane layer is intact, electrical resistance measurements can be made both before and after permeability assays are conducted. Intact hexadecane layers exhibit extremely high electrical resistance (normally exceeding 25 kΩ.). Data from wells with electrical resistance measurements below 5 kΩ should be excluded.

Note 3: An acceptor plate is included in the packaging of the permeability plate. Alternatively, the PTFE Acceptor plate (# MSSACCEPT0R) is recommended in place of the packaged acceptor plate.

Note 4: To avoid evaporation, the plate should be placed in humidity controlled environment such as a sealed container with wet paper towels during incubation.

Note 5: Generally sample analysis using a 96 well UV/Vis plate reader is recommended. Sample quantification techniques such as scanning over a broad absorbance range (e.g. 250-500 nm), a single wavelength (λmax) or a summation of pre-selected fixed wavelengths are all acceptable for analysis. HPLC-UV or LC-MS/MS are also alternative means of detection.



Wohnsland, F.; Faller, B. High-throughput Permeability pH Profile and High-throughput Alkane/Water Log P With Artificial Membranes, J. Med. Chem., 2001; 44, p. 923–930.
Kansy, M.; Senner, F.; Gubernator, K. Physicochemical High Throughput Screening: Parallel Artificial Membrane Permeation Assay in the Description of Passive Absorption Processes, J. Med. Chem., 1998; 41, p. 1007–1010.