AssayIndex

AX-2024-005558

Selank · 20 mg declared · Bachem Holding (Suzhou) Co., Ltd. · lot BCH-2407-M7005

FAILVERIFIED
Report ID
AX-2024-005558
Compound
Selank
Compound class
Neuroactive and cognitive peptides
Supplier
BCH — Bachem Holding (Suzhou) Co., Ltd.
Batch / lot
BCH-2407-M7005
Declared label claim
20mg
Laboratory
PeptideMeter
Assay date
05 Aug 2024
Submitted
08 Aug 2024
Quarter
2024-Q3
Submitter
n.trevino
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, 28 min gradient, 214 nm99.26% area≥ 99.0PASS
Total impuritiesRP-HPLC, sum of reported peaks0.74% area≤ 1.0PASS
Largest single impurityRP-HPLC — tuftsin fragment (−417 Da)0.41% area≤ 1.00PASS
Identity — theoretical monoisotopic masscalculated from molecular formula751.4402DaNOT TESTED
Identity — observed monoisotopic massLC-MS, high resolution (ESI-TOF/QTOF)751.4173DaNOT TESTED
Mass accuracyobserved vs theoretical-30.5ppm± 15FAIL
Total peptide contentby difference from the gravimetric mass balance87.38%w/wNOT TESTED
Target-compound contenttotal peptide content × purity86.73%w/wNOT TESTED
Gross fill (as weighed)five-place balance, under nitrogen22.54mg20 mg declaredNOT TESTED
Recovered target peptidegross fill × target content19.549mg20 mg claimNOT TESTED
Recovery against label claimrecovered ÷ claim97.7%90.0 – 110.0PASS
Water contentKarl Fischer, coulometric, duplicate6.86%≤ 12.0PASS
Counter-ion (acetate)anion-exchange ion chromatography5.19%≤ 10.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.57%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 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 calibration5.592.5 – 8.0PASS
Retention time (observed)RP-HPLC, 28 min gradient5.98min6.03 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.460.910.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²60,228≥ 20,000PASS
Resolution to nearest impurityvs diketopiperazine (−18 Da)1.68no 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.

0493898751481319750 Selank5.98 min · 99.26 % 5.40 same trace · ×100 vertical expansion, baseline-corrected · main peak off-scale reporting threshold 0.05 % area 051015202530 Retention time (min) Response (mAU)
Figure 1. RP-HPLC trace, 28 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 60,228, and skew follows the reported asymmetry factor of 0.91. 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 0.41 % impurity against a 99.26 % main peak is a line two pixels tall; the main peak runs off-scale there by design.
#PeakRTArea (µV·s)% areaΔ mass (Da)
1Selank — main peak5.984,824,34499.26
2tuftsin fragment (−417 Da)5.4019,9270.41-417.235
3des-Thr (−101 Da)5.746,8040.14-101.048
4acetyl adduct (+42 Da)6.305,8320.12+42.011
5diketopiperazine (−18 Da)6.153,4020.07-18.011
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 751.4402 Da, computed from C33H57N11O9. All ppm figures on this site are against monoisotopic values — see why that matters.

0255075100325425525625725825 [M+1H]1+752.42[M+2H]2+376.72 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 751.4173 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+376.7274376.7159-0.011556.6
1+752.4475752.4246-0.0229100.0
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 Fischer6.86
Counter-ion (acetate)ion chromatography5.19
Residual solvent + inorganic residueestimated0.57
Total peptide contentby difference87.38
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)99.599.26divergence +0.24 pp vs batch median
Total impurities (% area)0.500.74
Largest single impurity (% area)not stated0.41
Water (%)6.56.86
Counter-ion (%)not stated5.19
Peptide content (%w/w)not stated87.38
Endotoxin (EU/mg)not statednot determined
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
Retail purchase → submitter (ambient, 14 d) → laboratory (hand-carried, 9 d) → assay.
Assay date
05 Aug 2024
Submitted to the index
08 Aug 2024
Laboratory
PeptideMeter, Tallinn, Estonia
Method basis
28 min gradient · high-resolution MS
Verification status
VERIFIED
Section 6

Annotations 5

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.

ppm_error
A single excursion of this size against a clean run of prior results on the same instrument is a calibration event with a date on it. The laboratory's own sequence log would place it; the index does not hold one.
one_directional
Direction is the thing to watch, not roundness. Rounded declarations in this index sit above and below the independent median at close to equal rates, which is what scatter looks like.
coa_gap
Rounding convention is the least of what a certificate carries. Lot code, method, wavelength and release date are the fields that let a reader reconstruct the figure, and the index scores those separately on the documentation rubric.
If a rounding convention changes mid-series the certificates become non-comparable across the change. Worth checking the timeline page before pooling declared figures from different quarters.
Section 7

Related records

Same batch — lot BCH-2407-M7005 n=7

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2024-005556BCH-2407-M7005Janoshik2024-Q399.026.99Buyer-sourced1MARGINAL
AX-2024-005557BCH-2407-M7005PeptideMeter2024-Q399.326.9888.7Buyer-sourced2MARGINAL
AX-2024-005559BCH-2407-M7005PeptideMeter2024-Q398.896.80Buyer-sourced1FAIL
AX-2024-005560BCH-2407-M7005Janoshik2024-Q399.297.11Laboratory-retained1MARGINAL
AX-2024-005561BCH-2407-M7005PeptideMeter2024-Q398.986.69104.1Buyer-sourced1FAIL
AX-2024-005562BCH-2407-M7005Janoshik2024-Q399.426.83Buyer-sourced1MARGINAL
Other recent Selank records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043000GGPepsGGPE-2602-G3499PeptideMeter2026-Q398.688.1089.6Buyer-sourced1FAIL
AX-2026-042924GGPepsGGPE-2603-J2151Medutest2026-Q399.188.75100.1Buyer-sourced0PASS
AX-2026-042987GGPepsGGPE-2601-J2834Janoshik2026-Q299.699.5292.5Buyer-sourced0PASS
AX-2026-042770ERPERP-2605-M9199Janoshik2026-Q299.476.15101.1Buyer-sourced0PASS
AX-2026-042762ERPERP-2605-M9199Janoshik2026-Q299.306.0589.8Buyer-sourced1MARGINAL
AX-2026-042992GGPepsGGPE-2601-J2834Janoshik2026-Q299.679.70107.2Buyer-sourced0PASS
AX-2026-042985GGPepsGGPE-2601-J2834Janoshik2026-Q299.649.27105.7Buyer-sourced0PASS
AX-2026-042993GGPepsGGPE-2601-J2834Janoshik2026-Q299.929.59Supplier-supplied0PASS
Other recent BCH records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-043691BPC-157BCH-2603-L7768Janoshik2026-Q398.665.12Supplier-supplied1MARGINAL
AX-2026-043693BPC-157BCH-2603-L7768PeptideMeter2026-Q397.825.2194.9Buyer-sourced0FAIL
AX-2026-043686BPC-157BCH-2603-L7768VendorInvestigate2026-Q397.645.27Buyer-sourced0FAIL
AX-2026-043695BPC-157BCH-2603-L7768Janoshik2026-Q397.615.42Buyer-sourced0FAIL
AX-2026-043726N-Acetyl Semax AmideBCH-2602-E8475Janoshik2026-Q397.899.67104.2Buyer-sourced0FAIL
AX-2026-043688BPC-157BCH-2603-L7768Janoshik2026-Q397.945.56Buyer-sourced0FAIL
AX-2026-043658BPC-157BCH-2603-G6644Janoshik2026-Q398.454.37101.8Supplier-supplied0PASS
AX-2026-043692BPC-157BCH-2603-L7768VendorInvestigate2026-Q397.605.61Buyer-sourced0FAIL