A comparison of 4 amino phases representing 3-aminopropyl silica
batches with different amount of grafted functional groups was made. To evaluate the chromatographic properties of the adsorbents, the Tanaka test for hydrophilic stationary phases was used, and the retention of polar substances of various classes in HILIC mode was also studied. It is shown that even small changes in nitrogen content between different batches of 3-aminopropyl silica have a significant effect on the retention of polar analytes. Hydrophilicity of a substrate was shown to have the greatest effect on its chromatographic behavior, and its evaluation using the Tanaka test is the basis for a batch selection either for separation of particular classes of polar substances or for further modification aiming at obtaining new phases.