HPLC analysis of N-nitrosamino acids and N-nitrosodipeptides N-terminal in proline.

An attempt has been made to develop conditions for the analysis of some N-nitrosamino acids and N-nitrosodipeptides N-thermal in proline by means of high performance liquid chromatography with thermal energy detector (HPLC-TEA). Two HPLC columns have been tested; cyano and amine chemically bonded columns. Although both of them give positive results baseline separation all of the compounds investigated takes place only on the amine column. On the cyano column two of the compounds remains unresolved and two other are not completely separated. Increasing the temperature of the HPLC columns to 90 degrees C and 100 degrees C for the cyano and amine columns respectively dramatically increase their efficiency due to the syn and anti isomers merging.