Celsius°
PEPTIDES
Certificate of Analysis
Starfield Processing Limited · 111 New Union Street
Coventry CV1 2NT · England
Product
DSIP
Lot number
CP2606-2420
Catalogue number
CP-3006
Research area
Neurological & Cognitive
Date of manufacture
2026-06-02
Date of analysis
2026-06-07
Retest by
2029-05-22
Appearance
White lyophilised solid
Purity by RP-HPLC (area normalisation, 220 nm)
99.00%
Specification ≥ 98.7%
RELEASED
9/9 parameters within specification
Analytical results
| Test | Method | Specification | Result | Status |
|---|---|---|---|---|
| Appearance | Visual inspection | White to off-white lyophilised solid | White lyophilised solid | Pass |
| Identity | ESI-MS (positive ion) | [M+H]⁺ 849.82 ± 1.0 Da | 849.74 Da | Pass |
| Purity | RP-HPLC, 220 nm, C18 gradient | ≥ 98.7 % (area normalisation) | 99.00 % | Pass |
| Single largest impurity | RP-HPLC, 220 nm | ≤ 1.00 % | 0.580 % | Pass |
| Water content | Karl Fischer titration | ≤ 8.0 % | 2.1 % | Pass |
| Acetate content | Ion chromatography | ≤ 12.0 % | 8.5 % | Pass |
| Peptide content | Amino acid analysis | ≥ 70.0 % | 84.3 % | Pass |
| Bacterial endotoxin | LAL kinetic chromogenic | ≤ 0.50 EU/mg | 0.106 EU/mg | Pass |
| Solubility | Visual, per stated solvent | Soluble in sterile water to 2 mg/mL | Conforms | Pass |
Figure 1 · RP-HPLC chromatogram
C18, 4.6 × 250 mm, 5 µm. Water/acetonitrile gradient with 0.1% TFA over 20 minutes. Detection at 220 nm.
| Peak | Retention time | Area % | Assignment |
|---|---|---|---|
| 1 | 6.78 min | 0.420 | Oxidised analogue |
| 2 | 8.37 min | 99.000 | DSIP |
| 3 | 8.45 min | 0.580 | Deletion sequence |
Figure 2 · ESI mass spectrum
Positive ion electrospray. Observed charge states with theoretical comparison below.
Molecular formula
C35H48N10O15
Theoretical [M+H]⁺
849.82 Da
Observed [M+H]⁺
849.74 Da
Sequence
Trp-Ala-Gly-Gly-Asp-Ala-Ser-Gly-Glu
WAGGDASGE