AssayIndex

AX-2026-041763

Selank · 20 mg declared · Thermo Fisher Scientific (China) Co., Ltd. · lot TFS-{CAT}-1712

PASSPURITY ONLY
Report ID
AX-2026-041763
Compound
Selank
Compound class
Neuroactive and cognitive peptides
Supplier
TFS — Thermo Fisher Scientific (China) Co., Ltd.
Batch / lot
TFS-{CAT}-1712
Declared label claim
20mg
Laboratory
PeptideMeter
Assay date
16 May 2026
Submitted
27 May 2026
Quarter
2026-Q2
Submitter
t.moreau
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 nm99.87% area≥ 99.0PASS
Total impuritiesRP-HPLC, sum of reported peaks0.13% area≤ 1.0PASS
Largest single impurityRP-HPLC — des-Thr (−101 Da)0.08% area≤ 1.00PASS
Identitynot ordered on this submissionnot determinedrequired for VERIFIED statusNOT TESTED
Peptide contentnot ordered on this submissionnot determinedrequired to check label claimNOT TESTED
Water contentKarl Fischer, coulometric, duplicate8.20%≤ 12.0PASS
Counter-ion (acetate)anion-exchange ion chromatography5.42%≤ 10.0PASS
Residual solvent + inorganic residueestimated — see /methods/residual-solvents-q3c/0.52%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 after 90 s gentle swirling, no particulatesclear, no visible particulatesPASS
pH (reconstituted, 1 mg/mL)potentiometric, two-point calibration5.632.5 – 8.0PASS
Retention time (observed)RP-HPLC, 28 min gradient6.02min6.03 ± 0.25 (normalised)PASS
Peak asymmetry (10 % height)Ph. Eur. 2.2.460.980.80 – 1.50PASS
Plate count, main peakN = 5.54 (t/w½)²95,977≥ 20,000PASS
Resolution to nearest impurityvs diketopiperazine (−18 Da)2.11no 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.

06009120191802824038 Selank6.02 min · 99.87 % 5.78 same trace · ×200 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 95,977, and skew follows the reported asymmetry factor of 0.98. 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 0.08 % impurity against a 99.87 % 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 peak6.024,853,99299.87
2des-Thr (−101 Da)5.783,8880.08-101.048
3diketopiperazine (−18 Da)6.191,4580.03-18.011
4tuftsin fragment (−417 Da)5.449720.02-417.235
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 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)99.9099.87divergence +0.03 pp vs batch median
Total impurities (% area)0.100.13
Largest single impurity (% area)0.060.08
Water (%)7.08.20
Counter-ion (%)4.35.42
Peptide content (%w/w)88.1not determined
Endotoxin (EU/mg)0.14not 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 → third-party forwarder (1 d) → laboratory (courier, cold pack, 11 d) → assay.
Assay date
16 May 2026
Submitted to the index
27 May 2026
Laboratory
PeptideMeter, Tallinn, Estonia
Method basis
28 min gradient · high-resolution MS
Verification status
PURITY ONLY
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.

selection_bias
Provenance handles supplier selection. It does not handle submitter selection, which is the larger confounder and the one the index cannot measure.
lal_assay
No endotoxin figure on this record, which is true of roughly three quarters of the index. It is the one measurement that cannot be inferred from any other and the one most often omitted.
endotoxin_limit
A chromatogram bears on endotoxin not at all. Purity, identity, content and water can all be excellent on material carrying a substantial burden, and nothing on this page would show it.
Section 7

Related records

Same batch — lot TFS-{CAT}-1712 n=13

ReportLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041751TFS-{CAT}-1712Janoshik2026-Q299.768.1989.9Buyer-sourced2MARGINAL
AX-2026-041752TFS-{CAT}-1712Medutest2026-Q299.637.43Buyer-sourced1FAIL
AX-2026-041753TFS-{CAT}-1712Janoshik2026-Q299.677.4892.6Buyer-sourced0PASS
AX-2026-041754TFS-{CAT}-1712PeptideMeter2026-Q299.937.49Buyer-sourced0PASS
AX-2026-041755TFS-{CAT}-1712VendorInvestigate2026-Q299.937.37104.5Buyer-sourced0PASS
AX-2026-041756TFS-{CAT}-1712PeptideMeter2026-Q299.908.21103.7Buyer-sourced0PASS
AX-2026-041757TFS-{CAT}-1712Medutest2026-Q299.937.54Buyer-sourced0PASS
AX-2026-041758TFS-{CAT}-1712Janoshik2026-Q299.788.1097.6Buyer-sourced0PASS
AX-2026-041759TFS-{CAT}-1712Janoshik2026-Q299.938.13102.2Buyer-sourced0PASS
AX-2026-041760TFS-{CAT}-1712Janoshik2026-Q299.827.70Buyer-sourced0PASS
AX-2026-041761TFS-{CAT}-1712PeptideMeter2026-Q299.937.7991.8Buyer-sourced0PASS
AX-2026-041762TFS-{CAT}-1712Janoshik2026-Q299.757.24Buyer-sourced0PASS
Other recent Selank records in the index.
ReportSupplierLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-042858GGPepsGGPE-2603-J2447VendorInvestigate2026-Q398.878.8599.4Buyer-sourced0FAIL
AX-2026-042859GGPepsGGPE-2603-J2447PeptideMeter2026-Q398.929.48103.5Buyer-sourced0FAIL
AX-2026-041759TFSTFS-{CAT}-1712Janoshik2026-Q299.938.13102.2Buyer-sourced0PASS
AX-2026-042912GGPepsGGPE-2601-J3130Janoshik2026-Q299.759.4489.7Buyer-sourced1MARGINAL
AX-2026-041760TFSTFS-{CAT}-1712Janoshik2026-Q299.827.70Buyer-sourced0PASS
AX-2026-041752TFSTFS-{CAT}-1712Medutest2026-Q299.637.43Buyer-sourced1FAIL
AX-2026-042915GGPepsGGPE-2601-J3130PeptideMeter2026-Q299.5310.03Buyer-sourced0PASS
AX-2026-042910GGPepsGGPE-2601-J3130VendorInvestigate2026-Q299.629.21105.0Buyer-sourced0PASS
Other recent TFS records in the index.
ReportCompoundLotLabQuarterPurity %Water %Recovery %ProvenanceFlagsResult
AX-2026-041681CJC-1295 with DACTFS-{CAT}-9675PeptideMeter2026-Q398.823.67Buyer-sourced0PASS
AX-2026-041766BPC-157TFS-{CAT}-1156Janoshik2026-Q399.546.34Buyer-sourced1MARGINAL
AX-2026-041682CJC-1295 with DACTFS-{CAT}-9675Nordanalyt2026-Q398.943.24Buyer-sourced0PASS
AX-2026-041683CJC-1295 with DACTFS-{CAT}-9675Medutest2026-Q398.683.4697.0Buyer-sourced0PASS
AX-2026-041765BPC-157TFS-{CAT}-1156Janoshik2026-Q399.796.01Buyer-sourced0PASS
AX-2026-041680CJC-1295 with DACTFS-{CAT}-9675Medutest2026-Q399.182.85100.4Buyer-sourced0PASS
AX-2026-041691SemaglutideTFS-{CAT}-9744Janoshik2026-Q298.316.0791.4Buyer-sourced0PASS
AX-2026-041700SS-31 (Elamipretide)TFS-{CAT}-1142Medutest2026-Q299.752.2796.3Buyer-sourced0PASS