Background

The mucosa can be considered to be a simple lipid barrier. Figure 1 At equilibrium, the concentration of the unionized drug [HA] on either side of lipid barrier will be the same. Using equation (9), we can calculate the molar ratios of ionized drug [A-] to [HA] on each side of the membrane. in plasma: [A-] [HA] = 10(7.4 - 4.4) = 103 = 1000 ................
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