Implementation of Capillary Electrochromatography with the Formation of Hydrophilic Coatings Based on Polyelectrolytes on the Walls of a Bare Fused Silica Capillary

The analytical capabilities of physically adsorbed coatings based on polyelectrolytes—poly(diallyldimethylammonium chloride), poly(styrene sulfonate), and chitosan—created by sequentially depositing oppositely charged layers are identified. The results of electrophoretic separation of catecholamines, carboxylic acids, amino acids and their derivatives, nonsteroidal anti-inflammatory drugs, and β-blockers on the resulting coatings are compared with those of previously studied monolayer and multilayer chitosan-based coatings. The polyelectrolyte coating is shown to be more stable and capable of performing a greater number of analytical cycles (up to 50) while maintaining its performance characteristics. According to SEM data, the coating thickness is 16–22 nm. Higher enantioselectivity is achieved with polyelectrolyte coatings during the chiral separation of nonsteroidal anti-inflammatory drugs (ketorolac and ketoprofen).