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. : 30deg-C