L-Pro References and Link 1) S.A. Cohen, D.P. Michaud, Synthesis of a fluorescent derivatizing reagent, 6-aminoquinolyl-N-hydroxysuccinimidyl carbamate, and its application for the analysis of hydrolysate amino acids via high-performance liquid chromatography, Anal. Biochem. 211 (1993) 279-287. (http://www.ncbi.nlm.nih.gov/pubmed/8317704)