Advances of hydrogel-modified silica as the stationary phase in high-performance liquid chromatography

In chromatographic technology, the stationary phase is of paramount importance, with its properties intrinsically linked to both the separation performance and the mode of chromatography employed. The study of stationary phase modifiers has attracted considerable attention in the field of analytical chemistry due to their critical role in the separation process. Of late, hydrogels, characterized by a three-dimensional structure and multiple interaction sites, have been harnessed to augment the development of stationary phases for liquid chromatography. Hydrogel-modified silica stationary phases have demonstrated superior separation performance across various chromatographic modes, including hydrophilic interaction, reverse-phase, and ion exchange liquid chromatography. The evolution of these functionalized silica stationary phases holds significant importance in the fields of analytical chemistry and separation science. However, to date, there has been a lack of comprehensive reviews discussing the use of hydrogel-modified silica stationary phases in liquid chromatography. This review provides a succinct overview of the performance and recent advancements of hydrogel-modified silica stationary phases in high-performance liquid chromatography (HPLC). It also provides an in-depth discussion on the use of hydrogel-modified silica stationary phase composites for the separation of analytes in various chromatographic modes. Efficient separation and analysis of analytes crucial to life sciences and medicine, such as nucleoside bases, steroid hormones, antibiotics, pesticides, and environmental pollutants, can be achieved using various hydrogel-modified silica stationary phases. Finally, it outlines the challenges and prospects associated with the application of hydrogel-modified silica in separation science.