The Application of Multiplexed Microemulsion Electrokinetic Chromatography for the Rapid Determination of log Pow Values for Neutral and Basic Compounds
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چکیده
short timeframe, and rapid approaches are needed to assess log Pow values of these compounds (2,4,7). Several separation-based approaches for indirectly determining log Pow values in a rapid fashion have been reported, including reversed-phase high performance liquid chromatography (HPLC) (2,3,8–11), thin-layer chromatography (12,13), micellar electrokinetic chromatography (MEKC) (7,14–16), and microemulsion electrokinetic chromatography (3,4, 17–19). All of these approaches are based upon the construction of a correlation model between the logarithm of the thermodynamic capacity factor (log k), obtained using the separation technique, with known log Pow values obtained by the shake-flask method for a training set of compounds. The log Pow values for test compounds then are determined based upon their measured log k value using the mathematical relationship established for the training set. Relative to the shake-flask method, reversed-phase HPLC offers several advantages for the determination of log Pow values, including faster analysis times, improved The authors used multiplexed microemulsion electrokinetic chromatography with ultraviolet absorbance detection to develop a rapid approach for obtaining log P octanol–water (log Pow) values of neutral and basic compounds. By using a series of compounds (n 42) that covered a wide range of log Pow values, they established a universal calibration curve relating the log of retention factors (log k) obtained from multiplexed microemulsion electrokinetic chromatography to the known log Pow values. The log Pow values for additional compounds were obtained from their log k values by interpolating from the universal calibration curve. The multiplexed microemulsion electrokinetic chromatography performance for log Pow determinations was reproducible for multiple days and provided a rapid and accurate approach for obtaining log Pow values. The Application of Multiplexed Microemulsion Electrokinetic Chromatography for the Rapid Determination of log Pow Values for Neutral and Basic Compounds
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