AssayIndex

AX-2025-019344

Dihexa · 20 mg declared · Shenzhen Hybio Pharmaceutical Co., Ltd. · lot HYB-2501-T6290

PASSIDENTITY CONSISTENT
Report ID
AX-2025-019344
Compound
Dihexa
Compound class
Neuroactive and cognitive peptides
Supplier
HYB — Shenzhen Hybio Pharmaceutical Co., Ltd.
Batch / lot
HYB-2501-T6290
Declared label claim
20mg
Laboratory
Kestrel Bioanalytical
Assay date
14 Jun 2025
Submitted
15 Jun 2025
Quarter
2025-Q2
Submitter
s.bhattacharya
Sample provenance
Buyer-sourced
Section 1

Results

Measured against the index acceptance specification for the neuroactive and cognitive 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, 15 min gradient, 214 nm99.93% area≥ 98.5PASS
Total impuritiesRP-HPLC, sum of reported peaks0.07% area≤ 1.5PASS
Largest single impurityRP-HPLC — des-hexanoyl (−98 Da)0.04% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula504.3312DaNOT TESTED
Identity — observed monoisotopic massLC-MS, unit resolution (single quadrupole)504.3333DaNOT TESTED
Mass accuracyobserved vs theoretical+4.2ppm± 15PASS
Peptide contentnot ordered on this submissionnot determinedrequired to check label claimNOT TESTED
Water contentKarl Fischer, coulometric, duplicate6.63%≤ 12.0PASS
Counter-ionno ionisable counter-ion expectedN/Anot applicableNOT TESTED
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.70%NOT TESTED
Endotoxinnot ordered on this submissionnot determined≤ 5.0NOT TESTED
Sterilitynot ordered on this submissionnot determinedno growthNOT TESTED
Appearancevisual, diffuse light, black and white backgroundOff-white 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 calibration7.242.5 – 8.0PASS
Retention time (observed)RP-HPLC, 15 min gradient6.49min6.61 ± 0.30 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.461.070.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²71,101≥ 20,000PASS
Resolution to nearest impurityvs free acid (+1 Da)1.30no 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.

0459291841377618368 Dihexa6.49 min · 99.93 % 5.286.62 same trace · ×200 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 048121620 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 15 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 71,101, and skew follows the reported asymmetry factor of 1.07. 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 0.04 % impurity against a 99.93 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1Dihexa — main peak6.494,856,90899.93
2des-hexanoyl (−98 Da)5.281,9440.04-98.074
3free acid (+1 Da)6.621,4580.03+0.984
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 504.3312 Da, computed from C27H44N4O5. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100475500525550575 [M+1H]1+505.34 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 504.3333 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+505.3385505.34060.0021100.0
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.

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)99.6299.93divergence -0.02 pp vs batch median
Total impurities (% area)0.380.07
Largest single impurity (% area)0.140.04
Water (%)5.56.63
Counter-ion (%)6.6N/A
Peptide content (%w/w)87.3not determined
Endotoxin (EU/mg)not statednot determined
Method stated on certificateYEScolumn, 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 → submitter (ambient, 24 d) → laboratory (courier, cold pack, 12 d) → assay.
Assay date
14 Jun 2025
Submitted to the index
15 Jun 2025
Laboratory
Kestrel Bioanalytical, Melbourne, Australia
Method basis
15 min gradient · unit-resolution MS
Verification status
IDENTITY CONSISTENT
Section 6

Annotations 2

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.

buyer_sourced
Buyer-sourced through an ordinary retail order, so the supplier had no opportunity to select the vial. This is the provenance class the index weights and it is roughly 87 % of the dataset.
coa_reader
The certificate that arrives with a retail order is the certificate an ordinary buyer gets. Assessing it is assessing the real documentation practice rather than the sample-request one.
Section 7

Related records

Same batch — lot HYB-2501-T6290 n=6

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2025-019340HYB-2501-T6290Kestrel2025-Q299.717.1191.7Buyer-sourced0PASS
AX-2025-019341HYB-2501-T6290Janoshik2025-Q299.487.2693.6Buyer-sourced0PASS
AX-2025-019342HYB-2501-T6290VendorInvestigate2025-Q299.577.16Buyer-sourced1MARGINAL
AX-2025-019343HYB-2501-T6290VendorInvestigate2025-Q299.396.8396.2Buyer-sourced0PASS
AX-2025-019345HYB-2501-T6290Kestrel2025-Q299.936.79Buyer-sourced0PASS
Other recent Dihexa records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041370WWBWWB-2601-C4091Kestrel2026-Q299.9311.05Buyer-sourced0PASS
AX-2026-041521QSCQSC-2512-D5887Janoshik2026-Q299.646.16Laboratory-retained0PASS
AX-2025-018407WWBWWB-2507-N1598Janoshik2025-Q399.619.31Buyer-sourced0PASS
AX-2025-019342HYBHYB-2501-T6290VendorInvestigate2025-Q299.577.16Buyer-sourced1MARGINAL
AX-2025-018408WWBWWB-2507-N1598Janoshik2025-Q399.798.96Buyer-sourced0PASS
AX-2025-019343HYBHYB-2501-T6290VendorInvestigate2025-Q299.396.8396.2Buyer-sourced0PASS
AX-2025-019345HYBHYB-2501-T6290Kestrel2025-Q299.936.79Buyer-sourced0PASS
AX-2025-019340HYBHYB-2501-T6290Kestrel2025-Q299.717.1191.7Buyer-sourced0PASS
Other recent HYB records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042083MOTS-cHYB-2606-D7858Medutest2026-Q399.932.02Buyer-sourced0PASS
AX-2026-042090MOTS-cHYB-2606-D7858Janoshik2026-Q399.572.36Buyer-sourced1FAIL
AX-2026-042084MOTS-cHYB-2606-D7858Janoshik2026-Q399.282.79107.3Buyer-sourced0PASS
AX-2026-042087MOTS-cHYB-2606-D7858Janoshik2026-Q399.543.05Buyer-sourced0PASS
AX-2026-042085MOTS-cHYB-2606-D7858Janoshik2026-Q399.512.31Buyer-sourced0PASS
AX-2026-042088MOTS-cHYB-2606-D7858PeptideMeter2026-Q399.222.21Buyer-sourced0PASS
AX-2026-042086MOTS-cHYB-2606-D7858Janoshik2026-Q399.933.02Buyer-sourced1MARGINAL
AX-2026-042091CJC-1295 with DACHYB-2608-E7391Janoshik2026-Q399.385.53Buyer-sourced0PASS