Rapid estimation of octanol-water partition coefficient for triazole fungicides by MEKC with sodium deoxycholate as surfactant

Abstract

A rapid estimation of octanol-water partition coefficient (log P-ow) was developed for triazole fungicides by micellar electrokinetic chromatography (MEKC). Five standard compounds with known log P-ow values from 2.9 to 4.3 (cyproconazole, bromuconazole, epoxiconazole, bitertanol and difenoconazole) were used for constructing the calibration curve of the log P-ow against the MEKC retention factor, log k. A linear relationship was achieved between log P-ow and log k, in the MEKC system containing 40 mM sodium deoxycholate (SDC) and 4 mM borate buffer at pH 9.3, with a correlation of determination, r(2) = 0.9905. The log P-ow values of four test compounds of triazole fungicides (triadimenol, myclobutanil, propiconazole and penconazole) were calculated based on the log k values measured by MEKC and the slope and intercept of the calibration curve. This MEKC method can give good estimation of the log P-ow of the four test compounds of triazole fungicides with the differences between the literature log P-ow values and estimated log P-ow from the MEKC method were from 0.15 to 0.23 log units.