AX-2026-043667 · TB-500 · PPG lot PPG-2512-D8068

Section 1

Results

Measured against the index acceptance specification for the tissue-repair and immunomodulatory 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, 25 min gradient, 214 nm	99.41	% area	≥ 98.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.59	% area	≤ 1.5	PASS
Largest single impurity	RP-HPLC — des-acetyl TB-500 (−42 Da)	0.32	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	887.4964	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, unit resolution (single quadrupole)	887.4968	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+0.4	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	4.67	%	≤ 10.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	5.93	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.96	%	—	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	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	5.17	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 25 min gradient	7.16	min	6.65 ± 0.25 (normalised)	FAIL
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.11	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	40,637	—	≥ 20,000	PASS
Resolution to nearest impurity	vs [D-Thr]-diastereomer	0.63	—	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, 25 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 40,637, and skew follows the reported asymmetry factor of 1.11. 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 0.32 % impurity against a 99.41 % 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	TB-500 — main peak	7.16	4,831,634	99.41	—
2	des-acetyl TB-500 (−42 Da)	6.73	15,553	0.32	-42.011
3	[D-Thr]-diastereomer	7.07	8,749	0.18	0.000
4	des-Gln truncate (−128 Da)	6.96	2,430	0.05	-128.059
5	C-terminal amide (−1 Da)	7.31	1,944	0.04	-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 887.4964 Da, computed from C39H69N9O14. 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 887.4968 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 (%)
2+	444.7555	444.7557	0.0002	59.3
1+	888.5037	888.5041	0.0004	100.0

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)	99.34	99.41	divergence -0.05 pp vs batch median
Total impurities (% area)	not stated	0.59
Largest single impurity (% area)	not stated	0.32
Water (%)	3.3	4.67
Counter-ion (%)	not stated	5.93
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, 26 d) → laboratory (courier, dry ice, 4 d) → assay.
Assay date: 19 Jan 2026
Submitted to the index: 29 Jan 2026
Laboratory: Medutest, Ljubljana, Slovenia
Method basis: 25 min gradient · unit-resolution MS
Verification status: IDENTITY CONSISTENT

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.
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 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.

aspartimide29 Jan 2026

Aspartimide formation at an Asp-Gly or Asp-Ser motif shows up as a pair of late-eluting satellites. They are not present above the reporting threshold on this trace.

tbu_residual29 Jan 2026

Residual side-chain protection at +56 Da is the classic silent passenger on a high-purity trace. Nothing at that offset above threshold on this record.

mass_defect29 Jan 2026

Every named impurity on this record has a mass defect consistent with its structural assignment. That is the check that distinguishes an assignment from a guess.

Section 7

Related records

Same batch — lot PPG-2512-D8068 n=7

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043661	PPG-2512-D8068	PeptideMeter	2026-Q1	99.28	3.39	—	Buyer-sourced	0	PASS
AX-2026-043662	PPG-2512-D8068	PeptideMeter	2026-Q1	99.71	3.94	88.4	Buyer-sourced	1	MARGINAL
AX-2026-043663	PPG-2512-D8068	PeptideMeter	2026-Q1	99.39	4.46	102.4	Buyer-sourced	0	PASS
AX-2026-043664	PPG-2512-D8068	Janoshik	2026-Q1	99.24	3.87	100.6	Buyer-sourced	0	PASS
AX-2026-043665	PPG-2512-D8068	Kestrel	2026-Q1	99.20	3.37	89.9	Buyer-sourced	1	MARGINAL
AX-2026-043666	PPG-2512-D8068	Janoshik	2026-Q1	99.40	4.42	102.5	Buyer-sourced	0	PASS

Batch rollup and reproducibility assessment →

Cross-sections

Other recent TB-500 records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041776	ASY	ASY-{CAT}-2167	Janoshik	2026-Q3	99.92	4.61	98.2	Buyer-sourced	0	PASS
AX-2026-041777	ASY	ASY-{CAT}-2167	PeptideMeter	2026-Q3	99.78	4.09	92.8	Buyer-sourced	0	PASS
AX-2026-041782	ASY	ASY-{CAT}-2167	Nordanalyt	2026-Q3	99.93	3.94	—	Buyer-sourced	0	PASS
AX-2026-041774	ASY	ASY-{CAT}-2167	PeptideMeter	2026-Q3	99.93	4.41	96.2	Buyer-sourced	0	PASS
AX-2026-042127	JEEP	JEEP-2602-V8614	Medutest	2026-Q3	99.68	3.55	—	Buyer-sourced	1	FAIL
AX-2026-042021	AMB	AMB-2602-P5987	VendorInvestigate	2026-Q3	99.86	4.79	101.4	Buyer-sourced	0	PASS
AX-2026-041780	ASY	ASY-{CAT}-2167	Janoshik	2026-Q3	99.93	3.48	102.5	Buyer-sourced	1	FAIL
AX-2026-041779	ASY	ASY-{CAT}-2167	Janoshik	2026-Q3	99.84	3.85	—	Buyer-sourced	1	FAIL

Other recent PPG records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-043598	Tesamorelin	PPG-2608-A6835	Kestrel	2026-Q3	98.91	2.56	100.3	Buyer-sourced	1	FAIL
AX-2026-043597	Tesamorelin	PPG-2608-A6835	Janoshik	2026-Q3	98.54	1.15	—	Buyer-sourced	0	PASS
AX-2026-043596	Tesamorelin	PPG-2608-A6835	PeptideMeter	2026-Q3	98.74	1.83	105.1	Buyer-sourced	1	MARGINAL
AX-2026-043605	Retatrutide	PPG-2604-X7060	Janoshik	2026-Q2	98.17	4.29	99.7	Buyer-sourced	0	PASS
AX-2026-043601	Retatrutide	PPG-2604-X7060	Janoshik	2026-Q2	98.28	3.96	95.3	Buyer-sourced	0	PASS
AX-2026-043668	AOD-9604	PPG-2602-W8018	PeptideMeter	2026-Q2	99.47	3.06	—	Buyer-sourced	0	PASS
AX-2026-043670	AOD-9604	PPG-2602-W8018	PeptideMeter	2026-Q2	99.56	2.71	104.5	Buyer-sourced	0	PASS
AX-2026-043630	CJC-1295 (no DAC)	PPG-2512-D7211	Janoshik	2026-Q2	99.66	5.11	92.5	Buyer-sourced	0	PASS