App Note Title: A Look at Column Reproducibility: Endogenous Caffeine and Metabolites in Human Urine using Three Historical Batches of 1.8 um HSS T3 Stationary Phase

1. What are the unique structural features of the HSS T3 and what is the benefit of these features? (2 marks)
2. In the application note, three columns are analyzed, how do they differ? Why is it important to analyze columns which differ in this way (2 marks)
3. What aspect(s) of validation are being demonstrated by this study? (1 mark)
4. What aspects of the chromatogram were used for comparison? (1 mark) Why is each of these important (3 marks)
5. What was the importance of this work? Why is it worthwhile to do? (1 mark)