A student hydrolyses a sample of a tripeptide, Ala-Phe-Gly, to break it down into its constituent amino acids: alanine (Ala), phenylalanine (Phe), and glycine (Gly). The student analyses the resulting mixture using thin-layer chromatography (TLC).
State a suitable reagent and the reaction conditions required to hydrolyse the tripeptide.
During the TLC setup, the student uses a beaker containing a volatile organic solvent but forgets to cover the beaker with a lid. Identify why a lid is a necessary piece of apparatus and explain its purpose.
Explain why the different amino acids separate as they travel up the TLC plate.
The spots of the amino acids are originally invisible on the developed TLC plate. Name a suitable developing agent and explain why it is required.
In the final chromatogram: The distance from the base line to the solvent front is 8.0 cm8.0\text{ cm}8.0 cm. The distance from the base line to the centre of the phenylalanine (Phe) spot is 5.2 cm5.2\text{ cm}5.2 cm. Calculate the RfR_fRf value for phenylalanine.
