AssayIndex

AX-2025-020849

KPV · 20 mg declared · Chinese Peptide Company Co., Ltd. · lot CPC-2502-M2176

FAILIDENTITY CONSISTENT
Report ID
AX-2025-020849
Compound
KPV
Compound class
Tissue-repair and immunomodulatory peptides
Supplier
CPC — Chinese Peptide Company Co., Ltd.
Batch / lot
CPC-2502-M2176
Declared label claim
20mg
Laboratory
Medutest
Assay date
13 Aug 2025
Submitted
04 Sep 2025
Quarter
2025-Q3
Submitter
m.asante
Sample provenance
Buyer-sourced
Section 1

Results

Measured against the index acceptance specification for the tissue-repair and immunomodulatory 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, 25 min gradient, 214 nm98.49% area≥ 99.0FAIL
Total impuritiesRP-HPLC, sum of reported peaks1.51% area≤ 1.0FAIL
Largest single impurityRP-HPLC — Lys-Pro dipeptide (−99 Da)0.96% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula342.2267DaNOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)342.2270DaNOT TESTED
Mass accuracyobserved vs theoretical+0.9ppm± 15PASS
Total peptide contentby difference from the gravimetric mass balance83.55%w/wNOT TESTED
Target-compound contenttotal peptide content × purity82.29%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen25.52mg20 mg declaredNOT TESTED
Recovered target peptidegross fill × target content21.000mg20 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim105.0%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate2.77%≤ 10.0PASS
Counter-ion (acetate)anion-exchange ion chromatography13.46%≤ 12.0FAIL
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.22%NOT TESTED
Endotoxinkinetic chromogenic LAL0.94EU/mg≤ 5.0PASS
Sterilitynot ordered on this submissionnot determinedno growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundWhite lyophilised cake, intactwhite to off-white intact cakePASS
Reconstitution clarityreconstituted per submitter procedureClear, colourless, no visible particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.042.5 – 8.0PASS
Retention time (observed)RP-HPLC, 25 min gradient3.58min4.44 ± 0.20 (normalised)FAIL
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.010.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²59,789≥ 20,000PASS
Resolution to nearest impurityvs diketopiperazine (−18 Da)2.08no 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.

07748154962324430993 KPV3.58 min · 98.49 % 3.28 same trace · ×50 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 0481216202428 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 25 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 59,789, and skew follows the reported asymmetry factor of 1.01. 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 0.96 % impurity against a 98.49 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1KPV — main peak3.584,786,91998.49
2Lys-Pro dipeptide (−99 Da)3.2846,6590.96-99.068
3acetyl-KPV (+42 Da)3.8317,9830.37+42.011
4Pro-Val dipeptide (−128 Da)3.215,3460.11-128.095
5diketopiperazine (−18 Da)3.713,4020.07-18.011
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 342.2267 Da, computed from C16H30N4O4. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100300325350375400425 [M+1H]1+343.23 m/z Relative abundance (%)
Figure 2. ESI charge-state envelope, unit-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 342.2270 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 (%)
1+343.2340343.23430.0003100.0
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 Fischer2.77
Counter-ion (acetate)ion chromatography13.46
Residual solvent + inorganic residueestimated0.22
Total peptide contentby difference83.55
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)98.4498.49divergence +0.13 pp vs batch median
Total impurities (% area)not stated1.51
Largest single impurity (% area)not stated0.96
Water (%)2.32.77
Counter-ion (%)not stated13.46
Peptide content (%w/w)not stated83.55
Endotoxin (EU/mg)not stated0.94
Method stated on certificateNOno method section — the result cannot be reconciled against any other
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
Domestic warehouse despatch → submitter (2–8 °C, 4 d) → laboratory (courier, cold pack, 10 d) → assay.
Assay date
13 Aug 2025
Submitted to the index
04 Sep 2025
Laboratory
Medutest, Ljubljana, Slovenia
Method basis
25 min gradient · unit-resolution MS
Verification status
IDENTITY CONSISTENT
Section 6

Annotations 4

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.

gradient_25
Before treating 98.49 % as a process finding, check what it is being compared against. The index specification assumes the reference gradient; a figure taken on a different method is not automatically comparable to it.
spec_vs_result
The index specification is a threshold the index chose. A result below it is a measurement below a decision, not a regulatory status and not a safety statement. What it does establish is that this vial is not what the class specification describes.
lipidation_step
On an acylated compound the mono-ester by-product of the side-chain step is the impurity that most often carries a result into this band, and it is regiochemistry rather than sloppiness. The named table above will say whether that is what happened here.
nmr_qnmr
Mass at +0.9 ppm establishes identity but not content. Absolute content needs a standard or an orthogonal quantitative method, and neither is a mass spectrometer.
Section 7

Related records

Same batch — lot CPC-2502-M2176 n=11

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2025-020839CPC-2502-M2176Nordanalyt2025-Q398.142.79Buyer-sourced0FAIL
AX-2025-020840CPC-2502-M2176Janoshik2025-Q398.193.10Buyer-sourced0FAIL
AX-2025-020841CPC-2502-M2176Janoshik2025-Q398.313.2091.1Buyer-sourced0FAIL
AX-2025-020842CPC-2502-M2176Medutest2025-Q398.833.64Supplier-supplied1FAIL
AX-2025-020843CPC-2502-M2176Janoshik2025-Q398.083.15Buyer-sourced0FAIL
AX-2025-020844CPC-2502-M2176Medutest2025-Q398.603.40Buyer-sourced0FAIL
AX-2025-020845CPC-2502-M2176VendorInvestigate2025-Q398.583.63Buyer-sourced0FAIL
AX-2025-020846CPC-2502-M2176PeptideMeter2025-Q398.232.96Buyer-sourced0FAIL
AX-2025-020847CPC-2502-M2176Janoshik2025-Q399.253.41102.8Supplier-supplied1FAIL
AX-2025-020848CPC-2502-M2176Medutest2025-Q398.133.3297.4Buyer-sourced0FAIL
Other recent KPV records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042742GGPepsGGPE-2511-K1569Janoshik2026-Q298.405.09Buyer-sourced0FAIL
AX-2026-042259TFCTFC-2508-M9624Janoshik2026-Q199.933.3889.4Buyer-sourced1FAIL
AX-2026-042078HYBHYB-2511-P7317Nordanalyt2026-Q199.593.9298.8Buyer-sourced0PASS
AX-2026-042262TFCTFC-2508-M9624Janoshik2026-Q199.893.3292.2Buyer-sourced0FAIL
AX-2026-042260TFCTFC-2508-M9624PeptideMeter2026-Q199.932.8999.2Buyer-sourced0FAIL
AX-2026-042079HYBHYB-2511-P7317Janoshik2026-Q199.685.6794.7Buyer-sourced0FAIL
AX-2026-042257TFCTFC-2508-M9624Janoshik2026-Q199.542.8195.6Buyer-sourced0FAIL
AX-2026-042261TFCTFC-2508-M9624Medutest2026-Q199.933.2097.1Buyer-sourced0FAIL
Other recent CPC records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043319BPC-157CPC-2602-W1610Medutest2026-Q398.822.88103.5Buyer-sourced2MARGINAL
AX-2026-043295LiraglutideCPC-2602-G9942Janoshik2026-Q397.345.17106.3Buyer-sourced0FAIL
AX-2026-043288TirzepatideCPC-2607-L1516Janoshik2026-Q396.895.11101.1Laboratory-retained0FAIL
AX-2026-043327N-Acetyl Semax AmideCPC-2602-D1905Nordanalyt2026-Q399.055.6790.6Buyer-sourced1FAIL
AX-2026-043328N-Acetyl Semax AmideCPC-2602-D1905Janoshik2026-Q399.496.83100.9Supplier-supplied0PASS
AX-2026-043257L-CarnosineCPC-2603-G9615VendorInvestigate2026-Q398.2010.41102.2Buyer-sourced0FAIL
AX-2026-043297LiraglutideCPC-2602-G9942Janoshik2026-Q397.014.95103.5Buyer-sourced0FAIL
AX-2026-043331N-Acetyl Semax AmideCPC-2602-D1905Janoshik2026-Q399.466.22Supplier-supplied0PASS