Partitioning small unilamellar vesicles

Here, APsuv is the absorption potential measured from the distribution in small unilamellar vesicles (SUV) at pH 6.8, the solubility was measured at pH 6.8 in simulated intestinal fluid, V is the volume of intestinal fluid, and dose is a mean single oral dose. Liposome partitioning is only partly correlated with octanol/water distribution. 

AA Agbodjan, H Bui, MG Khaledi. Study of solute partitioning in biomem-brane-mimetic pseudophases by electrokinetic chromatography dihexadecyl phosphate small unilamellar vesicles. Langmuir 17 2893-2899 (2001). 

Tab. 4.1 Partitioning of ionizable drugs (see pKa) into small unilamellar vesicles (SUVs) of DOPC and into octanol for uncharged and charged species, determined by the potentiometric titration technique, compared with their intestinal absorption (%) at the doses indicated. (Adapted from Tab. 2 of ref. 16)... 

Second-derivative electronic absorption spectrophotometry, which is a method applied without any separation procedure, was used to determine the partition coefficients of three N-monodemethylated phenothiazine drugs, such as CPZ, triflupromazine and promazine, between the phosphatidylcholine bilayers of small unilamellar vesicles (SUVs) and water, in order to evaluate their affinity to biomembranes. The second-derivative spectra exhibited distinct isobestic points, confirming the entire elimination of the residual background signal effects of the SUVs which were observed in the conventional absorption spectra [161]. 

---