Repeatability and reproducibility of retention data and band profiles on reversed-phase liquid chromatographic columns II. Results obtained with Symmetry C-18 columns

The long-term repeatability, the column-to-column and the lot-to-lot reprod ucibilities of the retention and profile of the peaks obtained with 15 diff erent Symmetry C-18 columns were investigated. This packing material is an octadecyl bonded silica for RP-LC. Data characterizing the retention, the s teric selectivity, the hydrogen bonding capacity, the hydrophobic interacti on selectivity, the column efficiency, and the peak asymmetry are reported for a group of 30 neutral, acidic and basic compounds selected as probes. T hese data were acquired under five different sets of chromatographic condit ions, using an HP 1100 liquid chromatograph and following an experimental p rotocol previously described. Statistical comparison of five different colu mns of one batch and of columns representative of 10 different batches are based on the high precision data obtained. For example, for 28 of the 30 co mponents, the R.S.D.s of the retention factors measured on 10 columns from as many different batches were better than 2%. The R.S.D.s of the separatio n factors for 27 of these 30 components were below 1.4%. Such a level of co lumn reproducibility is most impressive. (C) 1999 Elsevier Science B.V. All rights reserved.