Choosing a stationary phase is the first step in developing a liquid chromatography (LC) separation method. Introducing a gradient in stationary phase functionality allows for tuning of analyte retention, translating to a possible improvement in selectivity and an increase in resolution versus that offered by uniform stationary phases. In this work, C18-silica, phenylbutyl-silica, and phenylbutyl-ammonium opposed continuous stationary phase gradients were fabricated using controlled rate infusion (CRI) on particle packed LC columns. Characterization of the stationary phase was carried out using spectroscopy and LC analysis to relate the ligand density gradient profile to the observed chromatographic parameters.
What will you learn?
- Constructive stationary phase gradients
- Destructive stationary phase gradients
- HPLC column characterization with Raman, IR, and TGA
Who may this interest?
- Separation scientists
- Bioanalytical and Analytical chemists
- Laboratory Technicians
- Laboratory Managers
Dr. Anna V. Forzano is a post-doctoral associate working in a pharmaceutical engineering lab (The Roper Lab) at Virginia Commonwealth University’s Engineering Department. The primary project Anna is involved with is titled Pharmacy On Demand, which involves the complete online synthesis and production of a solid oral dosage of the drug Ciprofloxacin. Anna’s role encompasses two main components: (1) leading the project’s efforts related to PAT (IR, Raman, and NIR) for online monitoring of concentration using PLS modeling in various reaction steps, along with the goal of using Raman to detect impurities in a later redissolution step, and (2) developing methods (GC-FID, GC-MS, LC-DAD, LC-MS, prepLC) for the various in-process and release testing associated with filing for an ANDA.