3. Results and discussion
3.1. Optimization of derivatization conditions
3.1.1. Effect of co-solvents and basic catalysts on derivatization CPMS was stable in common organic solvents. After keeping
the stock solution of CPMA in acetonitrile at room temperature for 1 week, the corresponding derivatization yields for fatty acids did not changed obviously with peak area deviations of less than 5%. Therefore, acetonitrile and some other solvents such as THF, DMF and DMSO were tested as co-solvents for the derivatization procedure. The results indicated that DMF gave the most intense fluorescence responses. The signal intensity obtained in DMF solution was about 140–200% of that in other solvents.