Thymosin Alpha-1 (Tα1) Testing & Verification
Independent, third-party verification of mail-in thymosin alpha-1 by reversed-phase HPLC. We confirm what your vial actually contains — identity, chromatographic purity, and net peptide content — reported on a certificate anyone can verify.
What Thymosin Alpha-1 is
Thymosin alpha-1 (Tα1), known generically as thymalfasin, is a synthetic 28-amino-acid peptide identical in sequence to a peptide first isolated from thymus tissue. Its N-terminus is acetylated and its average molecular weight is near 3,108 g/mol. The sequence is strongly acidic — nine of its 28 residues are aspartate or glutamate — which makes it one of the more polar peptides on the research market and sets where it elutes in reversed-phase chromatography. It contains no tryptophan, tyrosine or phenylalanine, so it is quantified at 214 nm, where the peptide backbone absorbs; the 280 nm trace is blank by design. It is unrelated to thymosin beta-4 and to TB-500 despite the shared name: a different sequence, a different mass and a different retention time. It is sold as a lyophilized research chemical and is not an FDA-approved drug in the United States; nothing about its identity, purity or content can be judged by eye.
Why get your Thymosin Alpha-1 independently tested
- Net peptide content vs. label mass: an acidic 28-residue peptide carries counter-ion and bound water, so the dry weight printed on the label routinely overstates the peptide present. The assay reports milligrams of peptide per vial, not milligrams of powder.
- Synthesis-related impurities: a 28-mer made by solid-phase synthesis accumulates deletion and truncation sequences, and a batch that skipped or only partly completed the N-terminal acetylation carries the des-acetyl peptide. These elute close to the main peak; purity by area percent separates a clean lot from one padded with near-neighbours.
- Degradation on storage: the sequence contains several aspartate residues and a C-terminal asparagine, sites prone to isomerization and deamidation in a vial that has been warm or damp. Those products show up as shoulders and satellite peaks beside the main peak.
- Name confusion: 'thymosin' on a label can mean thymosin alpha-1, full-length thymosin beta-4, or the TB-500 fragment. They are three different molecules. An identity match shows which one is actually in the vial.
What we measure on Thymosin Alpha-1
Every thymosin alpha-1 certificate reports three results by reversed-phase HPLC with UV/diode-array detection at 214 nm: identity (retention-time plus UV-spectral match to a thymosin alpha-1 reference standard), chromatographic purity as area percent, and net-peptide assay in milligrams of peptide per vial. We do not perform mass spectrometry, sterility, or endotoxin testing.
Every result is issued as a certificate of analysis you — or anyone you forward it to — can verify cryptographically. Reporting identity, purity, and milligram content is the point: a vial can be pure and still underfilled, so we report all three. More on purity vs. net-peptide content and how to read a peptide COA.
Our scope — stated plainly
Testing is RP-HPLC-UV against a reference standard and establishes identity, chromatographic purity, and net peptide content — not sterility, safety, or fitness for any use. A vial that turns out to hold a different thymosin (beta-4 or the TB-500 fragment) is reported as such, not certified as thymosin alpha-1.
KMD is an independent RP-HPLC-UV lab. We do not run LC-MS / mass-spec, sterility, endotoxin, or heavy-metal testing. If your job needs a capability we don't have, we'll say so.
Thymosin Alpha-1 testing — FAQ
Is thymosin alpha-1 the same as TB-500 or thymosin beta-4?
No. Thymosin alpha-1 is a 28-residue peptide of about 3,108 g/mol. Thymosin beta-4 is a 43-residue peptide and TB-500 is a 7-residue fragment of it. The three run against different reference standards and elute at different retention times, so order the one that matches your label.
Why is the 280 nm trace empty on my certificate?
Thymosin alpha-1 contains no tryptophan, tyrosine or phenylalanine, the residues that absorb near 280 nm, so a flat 280 nm trace is expected. Identity, purity and content are all read at 214 nm, where the peptide backbone absorbs.
My vial is labelled TA-1 or thymalfasin — is that this test?
Yes. TA-1, Tα1 and thymalfasin are all names for thymosin alpha-1. Choose Thymosin Alpha-1 on the order form and enter the amount printed on the label.
Do you confirm the sequence or the acetyl group by mass spec?
No. We use RP-HPLC-UV, which establishes identity by retention-time and UV-spectral match to a reference standard, not by molecular mass. We do not run LC-MS or any mass-spectrometric methods.
Related tests
Thymosin Beta-4 (full-length) · TB-500 · Retatrutide · Cagrilintide · Tesamorelin · see the full panel.
Thymosin Alpha-1 testing costs $150 per vial — $125/vial at 5+ vials, $100/vial at 10+ — for the full panel: identity, chromatographic purity, and assay. Rush results in 4 business days. Start an order or see the full rate card.