AX-2026-041437 · Thymosin α1 · QYB lot QYB-2511-V5408

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, 28 min gradient, 214 nm	99.75	% area	≥ 97.5	PASS
Total impurities	RP-HPLC, sum of reported peaks	0.25	% area	≤ 2.5	PASS
Largest single impurity	RP-HPLC — des-acetyl Tα1 (−42 Da)	0.18	% area	≤ 1.00	PASS
Identity — theoretical monoisotopic mass	calculated from molecular formula	3106.5493	Da	—	NOT TESTED
Identity — observed monoisotopic mass	LC-MS, high resolution (ESI-TOF/QTOF)	3106.5515	Da	—	NOT TESTED
Mass accuracy	observed vs theoretical	+0.7	ppm	± 15	PASS
Total peptide content	by difference from the gravimetric mass balance	90.99	%w/w	—	NOT TESTED
Target-compound content	total peptide content × purity	90.76	%w/w	—	NOT TESTED
Gross fill (as weighed)	five-place balance, under nitrogen	10.14	mg	10 mg declared	NOT TESTED
Recovered target peptide	gross fill × target content	9.203	mg	10 mg claim	NOT TESTED
Recovery against label claim	recovered ÷ claim	92.0	%	90.0 – 110.0	PASS
Water content	Karl Fischer, coulometric, duplicate	2.57	%	≤ 10.0	PASS
Counter-ion (acetate)	anion-exchange ion chromatography	5.92	%	≤ 12.0	PASS
Residual solvent + inorganic residue	estimated — see /methods/residual-solvents-q3c/	0.52	%	—	NOT TESTED
Endotoxin	kinetic chromogenic LAL	0.22	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	Off-white lyophilised cake, intact	—	white to off-white intact cake	PASS
Reconstitution clarity	reconstituted per submitter procedure	Faint haze, clearing on standing	—	clear, no visible particulates	FAIL
pH (reconstituted, 1 mg/mL)	potentiometric, two-point calibration	5.93	—	2.5 – 8.0	PASS
Retention time (observed)	RP-HPLC, 28 min gradient	11.96	min	11.94 ± 0.30 (normalised)	PASS
Peak asymmetry (10 % height)	Ph. Eur. 2.2.46	1.05	—	0.80 – 1.50	PASS
Plate count, main peak	N = 5.54 (t/w½)²	60,208	—	≥ 20,000	PASS
Resolution to nearest impurity	vs deamidated Asn (+1 Da)	1.59	—	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 60,208, and skew follows the reported asymmetry factor of 1.05. 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 0.18 % impurity against a 99.75 % 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	Thymosin α1 — main peak	11.96	4,848,159	99.75	—
2	des-acetyl Tα1 (−42 Da)	11.33	8,749	0.18	-42.011
3	deamidated Asn (+1 Da)	11.64	2,430	0.05	+0.984
4	aspartimide (−18 Da)	12.35	486	0.01	-18.011
5	truncated (1-24)	10.80	486	0.01	-487.229
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 3106.5493 Da, computed from C129H215N33O55. 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 3106.5515 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 (%)
5+	622.3171	622.3176	0.0005	8.8
4+	777.6446	777.6452	0.0006	54.1
3+	1036.5237	1036.5244	0.0007	100.0
2+	1554.2819	1554.2830	0.0011	50.6

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	2.57
Counter-ion (acetate)	ion chromatography	5.92
Residual solvent + inorganic residue	estimated	0.52
Total peptide content	by difference	90.99
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)	99.90	99.75	divergence +0.14 pp vs batch median
Total impurities (% area)	not stated	0.25
Largest single impurity (% area)	not stated	0.18
Water (%)	0.5	2.57
Counter-ion (%)	5.6	5.92
Peptide content (%w/w)	93.3	90.99
Endotoxin (EU/mg)	not stated	0.22
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 (ambient, 19 d) → laboratory (courier, cold pack, 7 d) → assay.
Assay date: 01 Mar 2026
Submitted to the index: 04 Mar 2026
Laboratory: PeptideMeter, Tallinn, Estonia
Method basis: 28 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 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.

sig_figs04 Mar 2026

Two decimal places on 99.75 % implies repeatability better than 0.01 pp, which no laboratory here claims. The number is sound; the printed precision is more than the method carries.

Index data team

Two decimal places are retained because the source reports carry them and truncating would discard information where a laboratory genuinely reports it. The uncertainty budget on /methods/uncertainty-budget/ is the right thing to read alongside any purity figure on this site.

peak_integrator04 Mar 2026

Nothing adverse on this record. Purity 99.75 %, largest single impurity des-acetyl Tα1 (−42 Da) at 0.18 %, and a mass balance that closes. It is a clean record and the index has no note to add to it.

quarter_over_quarter04 Mar 2026

Single records do not establish trends. Where this supplier's quarterly medians are stable across four quarters, a result like this reads as the process rather than the draw — and the timeline page is where to check that.

Section 7

Related records

Same batch — lot QYB-2511-V5408 n=12

Report	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041438	QYB-2511-V5408	Janoshik	2026-Q1	99.80	2.70	105.2	Buyer-sourced	0	PASS
AX-2026-041439	QYB-2511-V5408	PeptideMeter	2026-Q1	99.51	2.59	105.3	Buyer-sourced	0	PASS
AX-2026-041440	QYB-2511-V5408	VendorInvestigate	2026-Q1	99.81	3.10	101.9	Buyer-sourced	0	PASS
AX-2026-041441	QYB-2511-V5408	Janoshik	2026-Q1	99.68	2.72	—	Buyer-sourced	0	PASS
AX-2026-041442	QYB-2511-V5408	Kestrel	2026-Q1	99.82	2.35	96.1	Buyer-sourced	0	PASS
AX-2026-041443	QYB-2511-V5408	VendorInvestigate	2026-Q1	99.54	2.88	—	Buyer-sourced	0	PASS
AX-2026-041444	QYB-2511-V5408	PeptideMeter	2026-Q1	99.58	2.93	—	Buyer-sourced	0	PASS
AX-2026-041445	QYB-2511-V5408	VendorInvestigate	2026-Q1	99.93	2.73	—	Buyer-sourced	0	PASS
AX-2026-041446	QYB-2511-V5408	PeptideMeter	2026-Q1	99.40	2.66	98.9	Buyer-sourced	0	PASS
AX-2026-041447	QYB-2511-V5408	Janoshik	2026-Q1	99.93	2.34	—	Buyer-sourced	0	PASS
AX-2026-041448	QYB-2511-V5408	Janoshik	2026-Q1	99.77	2.54	89.9	Laboratory-retained	1	MARGINAL

Batch rollup and reproducibility assessment →

Cross-sections

Other recent Thymosin α1 records in the index.
Report	Supplier	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041996	AMB	AMB-2511-B5683	VendorInvestigate	2026-Q2	99.31	4.20	91.2	Buyer-sourced	0	PASS
AX-2026-041995	AMB	AMB-2511-B5683	PeptideMeter	2026-Q2	98.86	4.00	104.5	Buyer-sourced	0	PASS
AX-2026-041998	AMB	AMB-2511-B5683	Nordanalyt	2026-Q2	99.08	3.83	—	Buyer-sourced	0	PASS
AX-2026-043232	SGN	SGN-2512-Y9621	Janoshik	2026-Q2	99.42	6.88	89.1	Buyer-sourced	1	MARGINAL
AX-2026-041999	AMB	AMB-2511-B5683	Medutest	2026-Q2	99.93	3.95	102.2	Supplier-supplied	1	MARGINAL
AX-2026-041997	AMB	AMB-2511-B5683	PeptideMeter	2026-Q2	99.11	4.26	104.3	Buyer-sourced	0	PASS
AX-2026-041442	QYB	QYB-2511-V5408	Kestrel	2026-Q1	99.82	2.35	96.1	Buyer-sourced	0	PASS
AX-2026-041438	QYB	QYB-2511-V5408	Janoshik	2026-Q1	99.80	2.70	105.2	Buyer-sourced	0	PASS

Other recent QYB records in the index.
Report	Compound	Lot	Lab	Quarter	Purity %	Water %	Recovery %	Provenance	Flags	Result
AX-2026-041471	PT-141 (Bremelanotide)	QYB-2607-L4875	Janoshik	2026-Q3	99.72	3.75	101.7	Buyer-sourced	0	PASS
AX-2026-041377	Ipamorelin	QYB-2605-H3558	Nordanalyt	2026-Q3	99.93	4.35	—	Buyer-sourced	0	PASS
AX-2026-041427	Retatrutide	QYB-2604-B4920	PeptideMeter	2026-Q3	97.93	2.45	101.7	Buyer-sourced	0	PASS
AX-2026-041428	Retatrutide	QYB-2604-B4920	Janoshik	2026-Q3	98.35	3.20	—	Laboratory-retained	0	PASS
AX-2026-041473	PT-141 (Bremelanotide)	QYB-2607-L4875	PeptideMeter	2026-Q3	99.58	3.74	94.4	Buyer-sourced	0	PASS
AX-2026-041472	PT-141 (Bremelanotide)	QYB-2607-L4875	PeptideMeter	2026-Q3	99.93	3.94	—	Buyer-sourced	0	PASS
AX-2026-041429	Retatrutide	QYB-2604-B4920	Medutest	2026-Q3	98.53	2.69	99.8	Buyer-sourced	1	MARGINAL
AX-2026-041431	Retatrutide	QYB-2604-B4920	Janoshik	2026-Q3	98.63	2.32	94.2	Buyer-sourced	0	PASS