AX-2025-019171 · Tirzepatide · SinoPep lot SNP-2505-A3973

Section 1

Results

Measured against the index acceptance specification for the incretin analogues and co-agonists 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, 28 min gradient, 214 nm	98.73	% area	≥ 97.0	PASS
Total impurities	RP-HPLC, sum of reported peaks	1.27	% area	≤ 3.0	PASS
Largest single impurity	RP-HPLC — [D-Aib13]-diastereomer	0.88	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	4810.4103	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, high resolution (ESI-TOF/QTOF)	4810.6147	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+42.5	ppm	± 15	FAIL
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	5.03	%	≤ 8.0	PASS
Counter-ion (TFA)	anion-exchange ion chromatography	6.00	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.85	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	membrane filtration, USP <71>, 14 d	No growth at 14 d	—	no growth	PASS
Appearance	visual, diffuse light, black and white background	Off-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	3.60	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 28 min gradient	18.82	min	18.64 ± 0.45 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.16	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	55,239	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [D-Aib13]-diastereomer	0.54	—	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, 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 55,239, and skew follows the reported asymmetry factor of 1.16. 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 0.88 % impurity against a 98.73 % 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	Tirzepatide — main peak	18.82	4,798,584	98.73	—
2	[D-Aib13]-diastereomer	18.64	42,771	0.88	0.000
3	truncated (3-39)	17.44	12,151	0.25	-222.112
4	des-Aib2 analogue	18.49	2,916	0.06	-85.053
5	des-Gly deletion (−57 Da)	18.25	1,944	0.04	-57.021
6	tirzepatide dimer	22.53	1,458	0.03	+4810.410
7	C20 diacid mono-amide	20.33	486	0.01	+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 4810.4103 Da, computed from C225H348N48O68. 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 4810.6147 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 (%)
7+	688.2087	688.2379	0.0292	7.8
6+	802.7423	802.7764	0.0341	51.6
5+	963.0893	963.1302	0.0409	100.0
4+	1203.6099	1203.6610	0.0511	49.8
3+	1604.4774	1604.5455	0.0681	8.0

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.

Figure	Supplier COA	This report	Index note
Purity (% area)	98.88	98.73	divergence +0.16 pp vs batch median
Total impurities (% area)	not stated	1.27
Largest single impurity (% area)	not stated	0.88
Water (%)	4.2	5.03
Counter-ion (%)	4.2	6.00
Peptide content (%w/w)	91.0	not determined
Endotoxin (EU/mg)	0.69	not determined
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: Domestic warehouse despatch → submitter (2–8 °C, 2 d) → laboratory (courier, cold pack, 7 d) → assay.
Assay date: 19 May 2025
Submitted to the index: 02 Jun 2025
Laboratory: PeptideMeter, Tallinn, Estonia
Method basis: 28 min gradient · high-resolution MS
Verification status: IDENTITY CONSISTENT

What this report does not establish

How much of the named compound is in the vial. Peptide content was not determined, so recovered mass cannot be calculated and the label claim cannot be checked.
That the material is free of bacterial endotoxin. Endotoxin was not measured. No chromatographic result bears on it.
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 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.

ppm_error02 Jun 2025

+42.5 ppm is outside the class limit and outside what a calibrated instrument should produce at this mass. Before anyone reads it as a compound difference: calibration drift on PeptideMeter's side is far more likely. The chromatography is normal and retention at 18.82 min is where Tirzepatide belongs.

Index data team

Recorded as an identity-not-established finding rather than an identity failure, per rule AX-R01. A re-measurement has been requested from the submitter.

ms_confirm02 Jun 2025

The index records this as identity not established. That is a statement about the evidence, not about the material, and the distinction is the whole reason the status vocabulary has four values instead of two.

charge_envelope02 Jun 2025

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.

Section 7

Related records

Same batch — lot SNP-2505-A3973 n=5

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2025-019168	SNP-2505-A3973	PeptideMeter	2025-Q2	98.55	4.73	102.3	Buyer-sourced	PASS
AX-2025-019169	SNP-2505-A3973	Medutest	2025-Q2	98.48	5.13	99.4	Buyer-sourced	PASS
AX-2025-019170	SNP-2505-A3973	PeptideMeter	2025-Q2	98.72	4.08	—	Buyer-sourced	PASS
AX-2025-019172	SNP-2505-A3973	Janoshik	2025-Q2	98.98	4.48	—	Buyer-sourced	PASS

Batch rollup and reproducibility assessment →

Cross-sections

Other recent Tirzepatide records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Result
AX-2026-043288	CPC	CPC-2607-L1516	Janoshik	2026-Q3	96.89	5.11	101.1	Laboratory-retained	FAIL
AX-2026-041610	FGP	FGP-2603-L7753	Janoshik	2026-Q3	98.81	2.45	101.0	Buyer-sourced	PASS
AX-2026-041974	AMB	AMB-2603-C5112	Nordanalyt	2026-Q3	98.20	3.41	—	Buyer-sourced	PASS
AX-2026-041975	AMB	AMB-2603-C5112	Medutest	2026-Q3	97.88	3.45	106.9	Laboratory-retained	PASS
AX-2026-041609	FGP	FGP-2603-L7753	Janoshik	2026-Q3	98.52	2.00	98.0	Buyer-sourced	PASS
AX-2026-041978	AMB	AMB-2603-C5112	Janoshik	2026-Q3	97.94	3.57	103.0	Buyer-sourced	PASS
AX-2026-041982	AMB	AMB-2603-C5112	Janoshik	2026-Q3	97.60	4.46	—	Buyer-sourced	PASS
AX-2026-043286	CPC	CPC-2607-L1516	Kestrel	2026-Q3	98.20	4.56	—	Buyer-sourced	PASS

Other recent SinoPep records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041867	CJC-1295 with DAC	SNP-2607-C3886	Janoshik	2026-Q3	99.24	5.12	—	Laboratory-retained	1	FAIL
AX-2026-041913	Ipamorelin	SNP-2606-L4478	PeptideMeter	2026-Q3	98.88	5.28	—	Buyer-sourced	0	FAIL
AX-2026-041914	Ipamorelin	SNP-2606-L4478	Janoshik	2026-Q3	99.14	5.49	—	Buyer-sourced	0	PASS
AX-2026-041909	Ipamorelin	SNP-2606-L4478	PeptideMeter	2026-Q3	99.00	5.48	89.5	Buyer-sourced	1	MARGINAL
AX-2026-041895	Ipamorelin	SNP-2602-B3833	Janoshik	2026-Q3	99.93	4.72	105.9	Buyer-sourced	1	MARGINAL
AX-2026-041930	IGF-1 LR3	SNP-2606-D4620	Medutest	2026-Q3	98.54	5.37	93.8	Buyer-sourced	0	PASS
AX-2026-041898	Ipamorelin	SNP-2602-B3833	Nordanalyt	2026-Q3	99.93	4.54	96.0	Buyer-sourced	1	MARGINAL
AX-2026-041931	IGF-1 LR3	SNP-2606-D4620	PeptideMeter	2026-Q3	97.93	5.19	93.4	Buyer-sourced	0	PASS