Recovery of Peptides

In analyzing peptides using reversed phase columns (particularly ODS columns), there is always a concern about a decline in recovery. Therefore Asahipak ODP series should be used, which shows a better recovery in analyzing peptides of high, medium and low molecular weights as well as in analyzing acidic, neutral or basic peptides. The recovery of a number of peptides with a wide range of different characteristics are shown for isocratic elution conditions. With these columns it is possible to get a good recovery by isocratic elution.

Substance(1micro-g each)		MW	pI	HP	Recovery(%)
					Eluent A	Eluent B	Eluent C
Glu-Gly-Phe Substance P Frg.1-4	Acidic Basic	351 497	3.29 11.44	2.17 3.24	96 100	103 100	88 110
Met-Enkephalin Des-Arg9-Bradykinin	Neutral Basic	574 904	5.90 11.05	5.02 7.65	96 -	96 98	99 102
Substance P alpha-Endorphin	Basic Neutral	1348 1684	12 6.85	8.61 6.94	- -	90 96	105 100
beta-Endorphin Insulin B chain S-sulphonate Big gastrin (Human)	Basic Neutral Acidic	3465 3496 3749	9.93 6.05 4.32	16.80 24.05 23.53	- - -	- - -	100 97 95

PI: Isocratic point, HP: Hydrophorbic Parameter, Acidic: Acidic peptide, Neutral: Neutral peptide, Basic: Basic peptide

Column       : Shodex Asahipak ODP-50 6D (6.0mmID*150mm)
Eluent       : (A); 0.05% TFA aq./CH3CN=85/15
               (B); 0.05% TFA aq./CH3CN=80/20
               (C); 0.05% TFA aq./CH3CN=70/30
Flow rate    : 1.0mL/min
Detector     : UV(220nm)
Column temp. : 30°C