AssayIndex

AX-2025-018726

SS-31 (Elamipretide) · 10 mg declared · Qingdao Sigma Chemical Co., Ltd. · lot QSC-2502-M6829

FAILVERIFIED
Report ID
AX-2025-018726
Compound
SS-31 (Elamipretide)
Compound class
Metabolic and mitochondrial peptides
Supplier
QSC — Qingdao Sigma Chemical Co., Ltd.
Batch / lot
QSC-2502-M6829
Declared label claim
10mg
Laboratory
VendorInvestigate
Assay date
15 Sep 2025
Submitted
27 Sep 2025
Quarter
2025-Q3
Submitter
j.roos
Sample provenance
Buyer-sourced
Section 1

Results

Measured against the index acceptance specification for the metabolic and mitochondrial peptides class. A specification is a decision the index made; a result is a measurement. See where each threshold came from.

ParameterMethodResultUnitIndex spec
PurityRP-HPLC, 32 min gradient, 214 nm98.40% area≥ 98.5FAIL
Total impuritiesRP-HPLC, sum of reported peaks1.60% area≤ 1.5FAIL
Largest single impurityRP-HPLC — acetyl adduct (+42 Da)0.66% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula639.3856Da—NOT TESTED
Identity — observed monoisotopic massLC-MS, high resolution (ESI-TOF/QTOF)639.3837Da—NOT TESTED
Mass accuracyobserved vs theoretical-2.9ppm± 15PASS
Total peptide contentby difference from the gravimetric mass balance84.29%w/w—NOT TESTED
Target-compound contenttotal peptide content × purity82.94%w/w—NOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen12.60mg10 mg declaredNOT TESTED
Recovered target peptidegross fill × target content10.450mg10 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim104.5%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate5.35%≤ 9.0PASS
Counter-ion (acetate)anion-exchange ion chromatography9.45%≤ 12.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.91%—NOT TESTED
Endotoxinkinetic chromogenic LAL0.91EU/mg≤ 5.0PASS
Sterilitynot ordered on this submissionnot determined—no growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundOff-white lyophilised cake, intact—white to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulates—clear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.59—2.5 – 8.0PASS
Retention time (observed)RP-HPLC, 32 min gradient9.58min9.49 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.19—0.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²63,550—≥ 20,000PASS
Resolution to nearest impurityvs [D-Arg1]-epimer1.23—no index criterionREPORTED
Section 2

Chromatogram and peak integration

The figure is drawn from the table. It is not an independent illustration — if a number in the table changed, the trace would change with it.

027375475821210949 SS-31 (Elamipretide)9.58 min · 98.40 % 10.16 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 05101520253035 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 32 min gradient, 214 nm. Drawn from the peak-integration table below: peak positions are the reported retention times, peak areas are the reported area percentages, peak widths follow the reported plate count of 63,550, and skew follows the reported asymmetry factor of 1.19. Baseline noise is seeded from the report ID and is illustrative. The lower panel is the same trace at a stated vertical expansion with the slow gradient drift subtracted, because at full scale a 0.66 % impurity against a 98.40 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1SS-31 (Elamipretide) — main peak9.584,782,54598.40—
2acetyl adduct (+42 Da)10.1632,0780.66+42.011
3C-terminal free acid (+1 Da)9.7925,2740.52+0.984
4des-Dmt (−193 Da)8.8112,6370.26-193.110
5[D-Arg1]-epimer9.397,7760.160.000
Closure check — purity + Σ impurities 100.00CLOSES

Reporting threshold 0.05 % area. Peaks below it are not reported and are therefore excluded from the total, which overstates purity by their sum — see peak integration.

Section 3

Mass spectrum and identity

Theoretical monoisotopic mass 639.3856 Da, computed from C32H49N9O5. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100275350425500575650725 [M+1H]1+640.39[M+2H]2+320.70 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, high-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 639.3837 Da. Sodium (+21.982/z) and potassium (+37.956/z) adducts are shown where the parent charge state exceeds 25 % relative abundance; they are adducts of the same molecule and are not impurities.
ChargeTheoretical m/zObserved m/zΔ m/zRel. abundance (%)
2+320.7001320.6991-0.001052.1
1+640.3929640.3910-0.0019100.0
Section 4

Gravimetric mass balance

Water, counter-ion, residual and total peptide content are exhaustive and mutually exclusive categories. They must account for 100 % of the cake mass. The index closes this to within 0.02 pp and the build asserts it.

ComponentDetermination%w/w of cake
WaterKarl Fischer5.35
Counter-ion (acetate)ion chromatography9.45
Residual solvent + inorganic residueestimated0.91
Total peptide contentby difference84.29
Total100.00 CLOSES

Supplier certificate, as declared

The supplier's own figures for this lot, beside the independent measurement. Divergence is assessed against the batch median, not against this single report — see rule AX-R05.

FigureSupplier COAThis reportIndex note
Purity (% area)98.6098.40divergence +0.30 pp vs batch median
Total impurities (% area)1.401.60
Largest single impurity (% area)0.490.66
Water (%)3.65.35
Counter-ion (%)not stated9.45
Peptide content (%w/w)not stated84.29
Endotoxin (EU/mg)not stated0.91
Method stated on certificateYES—column, gradient and wavelength given
Section 5

Provenance and caveats

Where a sample came from changes the weight of the evidence. The index treats it as a first-class field.

Sample provenance
Buyer-sourced
Evidentiary weight
Strongest available evidence in this index.
Chain of custody
Retail purchase → third-party forwarder (12 d) → laboratory (courier, cold pack, 5 d) → assay.
Assay date
15 Sep 2025
Submitted to the index
27 Sep 2025
Laboratory
VendorInvestigate, Riga, Latvia
Method basis
32 min gradient · high-resolution MS
Verification status
VERIFIED
Section 6

Annotations 3

Signed technical comments from index contributors. Not a discussion forum — annotations question or contextualise the result, and the data team replies where a reply is warranted.

ms_confirm
-2.9 ppm at this mass is a clean identity confirmation. With retention at 9.58 min, SS-31 (Elamipretide) is established as the species measured. Note what it does not exclude: a mass-identical diastereomer, which no mass measurement of any resolution can.
mass_defect
Two instruments or it is not confirmed, and this record is one instrument. It is a good one instrument, and the index records it as confirmed rather than corroborated for that reason.
esi_tof
The observed monoisotopic mass on this record reconciles with the theoretical value to four decimal places, which is the arithmetic the index re-derives in its own build check rather than accepting from the report.
Section 7

Related records

Same batch — lot QSC-2502-M6829 n=8

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2025-018724QSC-2502-M6829Medutest2025-Q397.925.1297.3Buyer-sourced1FAIL
AX-2025-018725QSC-2502-M6829PeptideMeter2025-Q398.205.32107.5Buyer-sourced1FAIL
AX-2025-018727QSC-2502-M6829Janoshik2025-Q398.944.14—Supplier-supplied1MARGINAL
AX-2025-018728QSC-2502-M6829PeptideMeter2025-Q398.104.8498.2Buyer-sourced1FAIL
AX-2025-018729QSC-2502-M6829Medutest2025-Q398.614.22101.5Buyer-sourced1MARGINAL
AX-2025-018730QSC-2502-M6829VendorInvestigate2025-Q397.735.36101.7Buyer-sourced1FAIL
AX-2025-018731QSC-2502-M6829Kestrel2025-Q398.914.57—Buyer-sourced1MARGINAL

Cross-sections

Other recent SS-31 (Elamipretide) records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042222TFCTFC-2607-R9099VendorInvestigate2026-Q399.465.41102.6Buyer-sourced0PASS
AX-2026-042492HomopeptideHOMO-2604-D5484Medutest2026-Q399.932.40—Buyer-sourced0PASS
AX-2026-042226TFCTFC-2607-R9099Janoshik2026-Q399.625.47—Buyer-sourced0PASS
AX-2026-042491HomopeptideHOMO-2604-D5484Kestrel2026-Q399.933.24—Supplier-supplied0PASS
AX-2026-042495HomopeptideHOMO-2604-D5484PeptideMeter2026-Q399.933.22105.9Supplier-supplied0PASS
AX-2026-042220TFCTFC-2607-R9099Janoshik2026-Q399.834.90105.2Buyer-sourced0PASS
AX-2026-042344TFCTFC-2604-Y3208Janoshik2026-Q399.683.4395.9Buyer-sourced0PASS
AX-2026-042494HomopeptideHOMO-2604-D5484Kestrel2026-Q399.932.6996.0Buyer-sourced0PASS
Other recent QSC records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041599CJC-1295 (no DAC)QSC-2606-V7416VendorInvestigate2026-Q397.963.52—Buyer-sourced1FAIL
AX-2026-041601CJC-1295 (no DAC)QSC-2606-V7416Kestrel2026-Q398.334.10—Buyer-sourced1MARGINAL
AX-2026-041602CJC-1295 (no DAC)QSC-2606-V7416VendorInvestigate2026-Q398.363.38101.8Buyer-sourced1MARGINAL
AX-2026-041477TriptorelinQSC-2607-C5749Nordanalyt2026-Q399.533.42—Buyer-sourced0PASS
AX-2026-041600CJC-1295 (no DAC)QSC-2606-V7416Nordanalyt2026-Q397.744.91100.9Buyer-sourced1FAIL
AX-2026-041603CJC-1295 (no DAC)QSC-2606-V7416PeptideMeter2026-Q398.434.20—Buyer-sourced1MARGINAL
AX-2026-041606CJC-1295 (no DAC)QSC-2606-V7416Janoshik2026-Q398.033.58—Buyer-sourced1MARGINAL
AX-2026-041585LiraglutideQSC-2605-W7381Medutest2026-Q399.595.0992.8Laboratory-retained0PASS