Advancing Chromatography: Tailored Polyacrylamide Hydrophilic Stationary Phases with Adjustable Performance

In a new development, scientists at the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, have achieved a significant milestone in the field of chromatography by successfully tailoring polyacrylamide hydrophilic stationary phases to exhibit adjustable performance. This breakthrough offers promising prospects for advancing separation and analysis techniques. The findings of this study, led by Shudong Wang, have been published in the Journal of Chromatography A (1).

Multi-colored liquid in the vials | Image Credit: © luchschenF - stock.adobe.com

Polymer modified silica materials have long been used as stationary phases in hydrophilic-interaction chromatography (HILIC). However, the pursuit of stationary phases with exceptional performance has remained a priority for researchers. Addressing this challenge, the team of scientists embarked on synthesizing vinyl modified silica through a silane coupling reaction. Subsequently, they successfully prepared a polyacrylamide modified silica (PAM-SIL) stationary phase by employing acrylamide as a copolymer monomer through free radical polymerization.

To thoroughly explore the capabilities of the newly developed stationary phase, the researchers conducted extensive investigations into the retention behaviors of polar analytes under various chromatographic conditions. Factors such as acetonitrile content, buffer concentration, and pH values were taken into account during the analysis. As a result, a typical hydrophilic interaction retention mechanism was inferred, shedding light on the fundamental principles underlying the separation process.

Remarkably, the team discovered that the separation performance of the stationary phases could be regulated by carefully controlling the polymer structure. By adjusting the grafting amount of vinyl, the researchers achieved rapid separation of model analytes, with the highest number of theoretical plates (N/m) for orotic acid (uracil-6-carboxylic acid) reaching an impressive 119,966/m. Moreover, stationary phases with higher acrylamide concentrations exhibited enhanced retention behavior and yielded higher resolution for analytes. This unique feature of adjustable separation performance holds immense potential for future applications in various fields of separation and analysis.

The novel approach of tailoring polyacrylamide hydrophilic stationary phases with adjustable performance is poised to revolutionize chromatography techniques. The ability to customize the separation performance according to specific requirements opens up exciting possibilities for researchers and analysts seeking optimal separation and purification strategies. This advancement has significant implications for the fields of natural product chemistry, pharmaceutical research, and other areas that heavily rely on chromatographic techniques.

Reference

(1) Wang, X.; Cui, J.; Zhou, J.; Wang, S.; Gu. Y.; Liu, X.; Wang, S. Preparation of polyacrylamide hydrophilic stationary phases with adjustable performance. J. Chromatogr. A 2023, 1702, 464065. DOI: https://doi.org/10.1016/j.chroma.2023.464065