AX-2026-043386 · MOTS-c · WXT lot WXT-2511-P3368

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.

Parameter	Method	Result	Unit	Index spec
Purity	RP-HPLC, 32 min gradient, 214 nm	97.84	% area	≥ 98.0	FAIL
Total impurities	RP-HPLC, sum of reported peaks	2.16	% area	≤ 2.0	FAIL
Largest single impurity	RP-HPLC — bis-sulfoxide (+32 Da)	1.33	% area	≤ 1.00	FAIL
Identity — theoretical monoisotopic mass	calculated from molecular formula	2173.0918	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, high resolution (ESI-TOF/QTOF)	2173.0948	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+1.4	ppm	± 15	PASS
Total peptide content	by difference from the gravimetric mass balance	88.31	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	86.40	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	11.50	mg	10 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	9.936	mg	10 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	99.4	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	5.35	%	≤ 9.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	5.93	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.41	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	0.40	EU/mg	≤ 5.0	PASS
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	White lyophilised cake, intact	—	white to off-white intact cake	PASS
Reconstitution clarity	reconstituted per submitter procedure	Clear, colourless, no visible particulates	—	clear, no visible particulates	PASS
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	3.49	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 32 min gradient	10.98	min	11.06 ± 0.30 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.04	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	72,164	—	≥ 20,000	PASS
Resolution to nearest impurity	vs des-Met1 (−131 Da)	1.40	—	no index criterion	REPORTED

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.

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 72,164, and skew follows the reported asymmetry factor of 1.04. 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 1.33 % impurity against a 97.84 % main peak is a line two pixels tall; the main peak runs off-scale there by design.

#	Peak	RT	Area (µV·s)	% area	Δ mass (Da)
1	MOTS-c — main peak	10.98	4,755,327	97.84	—
2	bis-sulfoxide (+32 Da)	10.28	64,642	1.33	+31.990
3	Met1 sulfoxide (+16 Da)	10.57	27,218	0.56	+15.995
4	des-Met1 (−131 Da)	11.21	7,290	0.15	-131.040
5	deamidated (+1 Da)	10.66	5,832	0.12	+0.984
Closure check — purity + Σ impurities				100.00	CLOSES

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 2173.0918 Da, computed from C101H152N28O22S2. All ppm figures on this site are against monoisotopic values — see why that matters.

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 2173.0948 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.

Charge	Theoretical m/z	Observed m/z	Δ m/z	Rel. abundance (%)
4+	544.2802	544.2810	0.0008	8.4
3+	725.3712	725.3722	0.0010	51.0
2+	1087.5532	1087.5547	0.0015	100.0
1+	2174.0991	2174.1021	0.0030	50.3

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.

Component	Determination	%w/w of cake
Water	Karl Fischer	5.35
Counter-ion (acetate)	ion chromatography	5.93
Residual solvent + inorganic residue	estimated	0.41
Total peptide content	by difference	88.31
Total		100.00 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.

Figure	Supplier COA	This report	Index note
Purity (% area)	98.91	97.84	divergence +0.26 pp vs batch median
Total impurities (% area)	1.09	2.16
Largest single impurity (% area)	0.43	1.33
Water (%)	3.1	5.35
Counter-ion (%)	8.3	5.93
Peptide content (%w/w)	96.3	88.31
Endotoxin (EU/mg)	not stated	0.40
Method stated on certificate	YES	—	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 → submitter (2–8 °C, 3 d) → laboratory (courier, ambient, 6 d) → assay.
Assay date: 25 Apr 2026
Submitted to the index: 15 May 2026
Laboratory: VendorInvestigate, Riga, Latvia
Method basis: 32 min gradient · high-resolution MS
Verification status: VERIFIED

What this report does not establish

That the material is sterile. Sterility was not tested.
That any other vial in the same lot has the same composition. One vial was tested. Within-lot vial-to-vial variation in this index has a median of 0.28 pp and a 90th percentile of 0.74 pp.
That any other lot from the same supplier has the same composition. Batch-to-batch variation is larger than within-batch variation for every supplier here.
That the material is suitable for administration to a human or an animal. These are research compounds. No result on this site is a safety assessment and the index takes no position on use.
That the material was manufactured by the supplier that sold it. Contract synthesis is normal in this market and twenty-nine batches in the index fingerprint to a bulk from a different company than the one named on the label.

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.

peak_integrator15 May 2026

Purity 97.84 %, water 5.35 %, counter-ion 5.93 % acetate. Read together these say the cake is what it claims to be and the chromatographic homogeneity is the limiting property. That narrows the question usefully.

hilic_hana15 May 2026

Short and polar sequences are poorly served by reverse phase, and a low area-percent figure on one can be a method artefact rather than a material property. HILIC or ion pairing would settle it.

sodium_adduct15 May 2026

Adduct bookkeeping on this one is tidy. The sodium series is present at the expected intensity ratio and has not been counted as an impurity, which happens more often than it should.

survodutide_mixup15 May 2026

Where two compounds elute within a third of a minute, a mass at this accuracy is what separates them. Retention alone would not have.

Section 7

Related records

Same batch — lot WXT-2511-P3368 n=8

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043381	WXT-2511-P3368	Janoshik	2026-Q2	98.69	5.17	97.5	Buyer-sourced	1	MARGINAL
AX-2026-043382	WXT-2511-P3368	Medutest	2026-Q2	99.41	5.21	—	Supplier-supplied	1	MARGINAL
AX-2026-043383	WXT-2511-P3368	Janoshik	2026-Q2	98.46	4.70	—	Supplier-supplied	1	MARGINAL
AX-2026-043384	WXT-2511-P3368	Janoshik	2026-Q2	98.37	5.62	92.1	Buyer-sourced	2	MARGINAL
AX-2026-043385	WXT-2511-P3368	Janoshik	2026-Q2	98.87	5.18	106.0	Buyer-sourced	1	MARGINAL
AX-2026-043387	WXT-2511-P3368	PeptideMeter	2026-Q2	98.65	5.02	101.5	Buyer-sourced	1	MARGINAL
AX-2026-043388	WXT-2511-P3368	Medutest	2026-Q2	98.65	4.49	94.4	Laboratory-retained	1	MARGINAL

Batch rollup and reproducibility assessment →

Cross-sections

Other recent MOTS-c records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042083	HYB	HYB-2606-D7858	Medutest	2026-Q3	99.93	2.02	—	Buyer-sourced	0	PASS
AX-2026-042090	HYB	HYB-2606-D7858	Janoshik	2026-Q3	99.57	2.36	—	Buyer-sourced	1	FAIL
AX-2026-042084	HYB	HYB-2606-D7858	Janoshik	2026-Q3	99.28	2.79	107.3	Buyer-sourced	0	PASS
AX-2026-042087	HYB	HYB-2606-D7858	Janoshik	2026-Q3	99.54	3.05	—	Buyer-sourced	0	PASS
AX-2026-042085	HYB	HYB-2606-D7858	Janoshik	2026-Q3	99.51	2.31	—	Buyer-sourced	0	PASS
AX-2026-042088	HYB	HYB-2606-D7858	PeptideMeter	2026-Q3	99.22	2.21	—	Buyer-sourced	0	PASS
AX-2026-042086	HYB	HYB-2606-D7858	Janoshik	2026-Q3	99.93	3.02	—	Buyer-sourced	1	MARGINAL
AX-2026-042081	HYB	HYB-2606-D7858	Nordanalyt	2026-Q3	99.68	3.31	96.5	Laboratory-retained	0	PASS

Other recent WXT records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043376	Semaglutide	WXT-2604-C3248	Janoshik	2026-Q3	97.08	4.22	—	Buyer-sourced	1	MARGINAL
AX-2026-043429	L-Glutathione (reduced)	WXT-2605-B3833	Nordanalyt	2026-Q3	98.48	6.58	96.9	Supplier-supplied	1	FAIL
AX-2026-043347	Leuprolide	WXT-2604-K2596	PeptideMeter	2026-Q3	99.16	5.99	93.6	Buyer-sourced	0	PASS
AX-2026-043353	Leuprolide	WXT-2604-K2596	Janoshik	2026-Q3	99.19	4.90	95.3	Laboratory-retained	0	PASS
AX-2026-043345	Leuprolide	WXT-2604-K2596	Janoshik	2026-Q3	98.93	5.28	—	Buyer-sourced	0	PASS
AX-2026-043424	L-Glutathione (reduced)	WXT-2605-B3833	PeptideMeter	2026-Q3	98.37	6.86	—	Buyer-sourced	0	FAIL
AX-2026-043374	Semaglutide	WXT-2604-C3248	Janoshik	2026-Q3	97.00	3.56	—	Buyer-sourced	1	MARGINAL
AX-2026-043377	Semaglutide	WXT-2604-C3248	PeptideMeter	2026-Q3	97.20	4.08	—	Buyer-sourced	1	MARGINAL