vs : what is the difference?

01

At a glance

The main differences in one list:

• Origin: is a fragment of a protein described in human gastric juice in 1993; is based on thymosin beta-4, a protein found in most cells and sequenced in 1981.
• Size: 15 amino acids for . For , either a seven-residue acetylated fragment (Ac-LKKTETQ) or the full 43-residue protein, depending on the supplier.
• Identity: has one well-defined sequence (GEPPPGKPADDAGLV); the other name covers more than one molecule, so its COA identity result matters more.
• Research themes: gastrointestinal and tendon models for ; actin binding, cell migration and blood-vessel development for thymosin beta-4.
• Formats at Prism Labs: both as 5 mg or 10 mg vials and as premixed 10 mg nasal sprays.

Sources: [1] PubChem · reference structure · [2] Journal of Physiology (Paris) · 1993 · [3] PNAS · 1981 · [4] Journal of Chromatography A · 2012

02

Two separate origins

came from Predrag Sikirić’s group in Zagreb, which described a gastric-juice protein in 1993 and went on to study a stable 15-residue fragment of it. A 2025 review notes that most of the evidence still comes from animal studies.

Thymosin beta-4 was isolated from calf thymus and sequenced in 1981; in 1991 it was identified as the main actin-sequestering peptide in platelets. is a trade name for synthetic peptides based on it.

Sources: [2] Journal of Physiology (Paris) · 1993 · [9] Current Reviews in Musculoskeletal Medicine · 2025 · [3] PNAS · 1981 · [5] Journal of Biological Chemistry · 1991 · [4] Journal of Chromatography A · 2012

03

Where their research overlaps

Both have been studied in tissue-repair models, which is why they are often grouped. A 2011 study examined tendon cells in culture; a 2007 study examined thymosin beta-4 in coronary vessel development in mice.

In 2026, a rat Achilles-tendon study tested each peptide alone and the two combined. It is one of the few papers to study them side by side.

These are observations in laboratory models. They are not evidence about any use in people.

Sources: [6] Journal of Applied Physiology · 2011 · [7] Annals of the New York Academy of Sciences · 2007 · [8] Joint Diseases and Related Surgery · 2026

04

Sold together

Because they are researched in similar models, Prism Labs sells them individually and together as the . Each vial in the stack keeps its own lot and COA.

They also appear together in two blends: and .

05

What to check on each COA

Read each certificate for the lot number on your vial:

• : the identity result should match the 15-residue sequence and its mass.
• : the identity result shows whether the vial holds the seven-residue fragment or the full protein.
• Both: HPLC purity, and measured content against the label.

Step by step: how to read a peptide COA.