Lipophilicity determination of acidic compounds: MEEKC as a reliable high-throughput methodology
In the present study a pressure-assisted MEEKC method with reversed-polarity using a conventional CE instrument with UV detection and uncoated fused silica capillaries is validated as a high-throughput methodology for the lipophilicity determination of the neutral species of acidic compounds (pK<sub>a</sub> > 3.5). After the calibration of the system with four standard compounds of known log P<sub>o/w</sub>, mass distribution ratios (log k<sub>MEEKC</sub>) of new molecules can be directly converted into log P<sub>o/w</sub> values by means of a simple linear equation (log P<sub>o/w</sub>=a·log k<sub>MEEKC</sub>+b). The method was internally and externally validated for a log P<sub>o/w</sub> range between -1.54 and 4.75, with higher accuracies than conventional liquid chromatographic methods.