HPLC Separation of Phenolic Acids on Silica Gels Layer-by-Layer Modified with 6,10-Ionene and Dextran Sulfate

Figure 5

Effect of pH on the retention of PA on SP-2. Acids (100 μg/ml): 1, caffeic; 2, ferulic; 3, -coumaric; 4, sinapic; 5, vanillic; 6, gallic; 7, salicylic; 8, sorbic; 9, benzoic.