Source comparison
TB-500 Fragment vs Full-Length Thymosin Beta-4 in Capsules
Most capsule products contain TB-500 (a 17-amino-acid fragment of the full 43-amino-acid Thymosin Beta-4 molecule). Some capsules claim to contain full-length Tb4. The distinction matters for oral delivery. A 17-amino-acid fragment may resist GI degradation so
This comparison does not assign a generated winner or score.
- Most capsule products contain TB-500 (a 17-amino-acid fragment of the full 43-amino-acid Thymosin Beta-4 molecule). Some capsules claim to contain full-length Tb4.
- The distinction matters for oral delivery. A 17-amino-acid fragment may resist GI degradation somewhat better than the full 43-amino-acid protein, simply because shorter peptides have fewer cleavage sites. However, no comparative oral bioavailability data exists for either form.
- Full-length Tb4 costs more to synthesize. If a vendor is charging significantly less than competitors for "TB-500 capsules," they are likely using a fragment. Check the label for the specific amino acid count or the descriptor "fragment (17-39)" which identifies the active TB-500 region.