| Abstract: | The correlation between the retention of 29 aromatic compounds on phenyl and octadecyl silica gel with their n-octanol-water partition coefficients has been studied. The work also covered the influence of mobile phase buffers and the effect on the correlation of using k′ values extrapolated to 100% water. The results show that the retention on phenyl silica correlates significantly better than that on octadecyl silica. The error in the prediction of log P, ranging from 1 to 8, from retention data on phenyl silica at a 95% confidence limit was found to be ±0.04 log units at log P = 4, and ±0.07 log units at log P = 7 when extrapolated k′ values were used. When k′ values measured at one fixed mobile phase composition were used, the error was found to be ±0.10 and ±0.16 log units at log P = 4 and 7, respectively. |
