AX-2024-004872 · Tirzepatide · ERP lot ERP-2406-E9182

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, 15 min gradient, 214 nm	98.43	% area	≥ 97.0	PASS
Total impurities	RP-HPLC, sum of reported peaks	1.57	% area	≤ 3.0	PASS
Largest single impurity	RP-HPLC — C20 diacid mono-amide	0.98	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	4810.4103	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	4810.3689	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	-8.6	ppm	± 15	PASS
Peptide content	not ordered on this submission	not determined	—	required to check label claim	NOT TESTED
Water content	Karl Fischer, coulometric, duplicate	4.31	%	≤ 8.0	PASS
Counter-ion (TFA)	anion-exchange ion chromatography	9.64	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.16	%	—	NOT TESTED
Endotoxin	not ordered on this submission	not determined	—	≤ 5.0	NOT TESTED
Sterility	not ordered on this submission	not determined	—	no growth	NOT TESTED
Appearance	visual, diffuse light, black and white background	White to pale-yellow 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	2.43	—	2.5 – 8.0	FAIL
Retention time (observed)	RP-HPLC, 15 min gradient	10.71	min	10.72 ± 0.45 (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	64,326	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [D-Aib13]-diastereomer	0.55	—	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, 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 64,326, 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 0.98 % impurity against a 98.43 % 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	10.71	4,784,003	98.43	—
2	C20 diacid mono-amide	11.52	47,631	0.98	+0.984
3	truncated (3-39)	9.97	17,011	0.35	-222.112
4	[D-Aib13]-diastereomer	10.62	8,263	0.17	0.000
5	trifluoroacetyl adduct (+96 Da)	11.18	1,944	0.04	+95.982
6	des-Aib2 analogue	10.54	972	0.02	-85.053
7	Met(O) sulfoxide (+16 Da)	10.34	486	0.01	+15.995
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, unit-resolution instrument. Sticks are placed at m/z = (M + z × 1.007276)/z for the observed neutral mass of 4810.3689 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	688.2028	-0.0059	9.0
6+	802.7423	802.7354	-0.0069	55.5
5+	963.0893	963.0811	-0.0082	100.0
4+	1203.6099	1203.5995	-0.0104	56.1
3+	1604.4774	1604.4636	-0.0138	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)	98.35	98.43	divergence +0.16 pp vs batch median
Total impurities (% area)	1.65	1.57
Largest single impurity (% area)	not stated	0.98
Water (%)	2.5	4.31
Counter-ion (%)	not stated	9.64
Peptide content (%w/w)	not stated	not determined
Endotoxin (EU/mg)	not stated	not determined
Method stated on certificate	NO	—	no 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 (−20 °C, 25 d) → laboratory (courier, dry ice, 6 d) → assay.
Assay date: 14 Sep 2024
Submitted to the index: 29 Sep 2024
Laboratory: Kestrel Bioanalytical, Melbourne, Australia
Method basis: 15 min gradient · unit-resolution MS
Verification status: METHOD LIMITED

What this report does not establish

That the compound is not a near-isobaric alternative. Identity was confirmed at unit mass resolution, which cannot exclude species differing by 1 or 2 Da. The specific alternatives not excluded are named in the identity block above.
That mass-identical impurities are absent. The gradient used is shorter than the index reference method and does not resolve the diastereomers named in the compound fingerprint. The purity figure is an upper bound.
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 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 1

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.

hplc_ola29 Sep 2024

A longer gradient buys resolution on close-eluting pairs at a linear cost in run time. Kestrel ran 15 min here; the reference method runs 30, and the difference is visible in this figure.

Section 7

Related records

Same batch — lot ERP-2406-E9182 n=11

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2024-004870	ERP-2406-E9182	Janoshik	2024-Q3	98.36	4.14	97.8	Buyer-sourced	0	PASS
AX-2024-004871	ERP-2406-E9182	Medutest	2024-Q3	98.19	4.20	—	Buyer-sourced	1	FAIL
AX-2024-004873	ERP-2406-E9182	PeptideMeter	2024-Q3	98.01	4.74	—	Buyer-sourced	0	PASS
AX-2024-004874	ERP-2406-E9182	Janoshik	2024-Q3	97.93	3.85	—	Buyer-sourced	0	PASS
AX-2024-004875	ERP-2406-E9182	Medutest	2024-Q3	98.24	4.71	—	Buyer-sourced	0	PASS
AX-2024-004876	ERP-2406-E9182	Janoshik	2024-Q3	97.95	3.96	97.3	Buyer-sourced	0	PASS
AX-2024-004877	ERP-2406-E9182	PeptideMeter	2024-Q3	97.96	4.27	—	Laboratory-retained	0	PASS
AX-2024-004878	ERP-2406-E9182	Medutest	2024-Q3	98.87	4.29	—	Supplier-supplied	0	PASS
AX-2024-004879	ERP-2406-E9182	VendorInvestigate	2024-Q3	97.62	4.65	106.5	Buyer-sourced	0	PASS
AX-2024-004880	ERP-2406-E9182	PeptideMeter	2024-Q3	98.26	3.90	99.5	Supplier-supplied	0	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 ERP records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-042706	Survodutide	ERP-2605-E9865	PeptideMeter	2026-Q3	98.38	5.33	103.5	Buyer-sourced	0	PASS
AX-2026-042704	Tesamorelin	ERP-2604-W9463	Janoshik	2026-Q3	99.02	4.08	—	Buyer-sourced	1	MARGINAL
AX-2026-042705	Survodutide	ERP-2605-E9865	Janoshik	2026-Q3	98.24	5.36	92.3	Buyer-sourced	0	PASS
AX-2026-042708	GHK-Cu	ERP-2601-F9816	Nordanalyt	2026-Q2	98.88	3.87	91.5	Buyer-sourced	1	MARGINAL
AX-2026-042694	Liraglutide	ERP-2601-P8985	Kestrel	2026-Q2	99.25	4.35	107.3	Buyer-sourced	1	MARGINAL
AX-2026-042707	GHK-Cu	ERP-2601-F9816	Janoshik	2026-Q2	98.53	4.70	96.3	Buyer-sourced	1	MARGINAL
AX-2026-042711	GHK-Cu	ERP-2601-F9816	Kestrel	2026-Q2	98.53	3.84	89.7	Laboratory-retained	2	MARGINAL
AX-2026-042722	Tirzepatide	ERP-2512-T9616	Medutest	2026-Q2	99.18	2.07	—	Buyer-sourced	1	MARGINAL