Reducing pressure and increasing peak capacity by incorporating an adaptable flow stream splitting platform to high-performance liquid chromatography columns: A study on C18 silica-based monoliths

In this study, an adaptable end-column platform was fitted to a commercially available monolith, which enabled the column to be fitted with a flow-splitting device. A variety of flow-splitting adapters could be incorporated into the platform, and in this study, a radial flow stream splitter was utilized. The advantage of the radial flow stream spitter was that it overcame issues relating bed density variations that could cause bands to distort in the radial cross-section of the column. Using propylbenzene as a test standard in isocratic elution mode, height equivalent to a theoretical plate curves were constructed across ten flow rates, and it was found that the column efficiency improved by as much as 73%. Furthermore, the dual outlet flow splitter enabled a very substantial reduction in column back pressure, with the decrease being consistently between 20 to 30% depending on the column length. Additionally, sensitivity increased by 45%, consistent with the observed increase in efficiency. The adaptable end-column platform could be retrofitted to almost any commercial column with the expectation of gaining efficiency, sensitivity, and reducing back pressure.