PAMPA lipid models table

In the rest of the chapter, we describe over 50 specific PAMPA lipid models developed at pION, identified in Table 7.3. The lipid models are assigned a two... 

Tables 7.6-7.8 list the Pe, SD, and %R of the 32 probe molecules in the thirteen new PAMPA lipid models, one of which is 2% DOPC assayed under sink conditions (model 1.1). The latter model served as a benchmark for assessing the effects of negative membrane charge.

The examination of over 50 PAMPA lipid models has led to an optimized model for gastrointestinal tract (GIT) absorption. Table 7.22 shows six properties of the GIT, which distinguish it from the blood-brain barrier (BBB) environment. 

Table 7.23 shows the results for 47 specific PAMPA models tested at pION, according the the scheme in Fig. 7.58. The two columns on the right are the r2 values in the comparisons. The neutral-lipid models (1.0, 1A.0, 2.0, 3.0, and 4.0) at pH 7.4 do not explain the permeability trend indicated in the human jejunal permeabilities [56]. Octanol was least effective, with r2 0.01. This should not be too surprising, since we did note that the appearance of naproxen, ketoprofen, and piroxicam at the top of the HJP ordering was unexpected. Our expectations were based on the octanol-water lipophilicity scale, which clearly does not correlate with the HJP trend. Adding a sink condition to the 2% DOPC model (model 1.1) improves correlation (r1 increases from 0.33 to 0.53). The addition of cholesterol to the 2% DOPC/dodecane system made the model unstable to the surfactant-created sink condition. 

TABLE 7.6 Two-Component Anionic Lipid PAMPA Models (with Sink), pH lAa... 

TABLE 7.9 Five-Component Anionic Lipid PAMPA Model (without Sink), pH 7.4a... 

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