Opioid peptides were analyzed using Asahipak ODP-50 6D by pre-column reaction method.


Sample :
1. Tyr-Gly-Gly-Phe
2. ME, Met-Enkephalin
3. LE, Leu-Enkephalin
4. LE-Arg
5. α-EDP, α-Endorphin
6. LE-NH₂
7. DNP 1-7
8. [D-Ala²] LE-NH₂
9. ME-Arg-Gly-Leu
10. γ-EDP
11. ME-Arg-Phe
12. DNP 1-8
13. β-NED, β-Neoendorphin
14. α-NED, β-NED-Lys
15. DNP 1-9
16. DNP 1-10
17. DNP-B

Column       : Shodex Asahipak ODP-50 6D (6.0 mm I.D. x 150 mm)
Eluent       : (A); 0.1 M Borate buffer (pH9.5)/H2O/CH3CN=10/39/1
               (B); 0.1 M Borate buffer (pH9.5)/H2O/CH3CN=2/3/5
               Gradient:(A) to (B)
Flow rate    : (0 to 25 min); 0.8 mL/min,
               (25 to 55 min); 1.0 mL/min,
               (after 55 min); 0.8 mL/min 
Detector     : Fluorescence (Ex. 330 nm, Em. 430 nm)
Column temp. : Room temp.

Guo-Qing Zhang et al., Chem. Pharm. Bull., 39 (1991) 126.