Homework Questions- Zirconia based stationary phases for HPLC

1. A chemist is running a column to separate proteins using a PBD-ZrO2 column. The mobile phase is composed of aqueous acetate buffer with THF as the organic modifier. Extremely broad peaks result. What is the most likely cause of the peak broadening and how can you change the mobile or stationary phase to help narrow the peaks? Hint: proteins contain carboxyl groups

2. Name some differences between zirconia and silica and give 2 advantages over silica

3. What is one way to increase elution efficiency on a zirconia based column if peaks are very well resolved?

4. A chemist is trying to separate enantiomers. Which non-bonded zirconia modification could they use to achieve separation?