Table 11.10.5.

Optimizing the Separation of PTH Amino Acids

Problem	Corrective action
Rise in baseline late in chromatogram	Add small aliquots of 1% acetone to buffer A
Negative baseline between DTT and Glu	Add small aliquots of 1.0 M KH2PO4 to buffer A
His too close to Ala or eluting after Ala	Increase Premix in buffer A
Arg too close to Tyr or eluting after Tyr	Increase Premix in buffer A
Ile/Lys not well separated (Lys early)	Decrease %B at 18-min point in gradient
Lys/Leu not well separated (Lys late)	Increase %B at 18-min point in gradient