BPC-157 vs TB-500: Structure, Sequence and Specifications

Introduction

BPC-157 and TB-500 are separate peptide specifications, not alternate names for one material. Comparing them starts with sequence notation, molecular formula, molecular weight, and the amount declared on each sealed vial. Their shared powder format does not make their chemical identities interchangeable. This guide keeps the comparison centered on those identifiers and the documents needed to track them.

The listed single-component products each contain 10 mg of lyophilized powder in a sealed glass vial. That matching label amount is a mass comparison only. It does not imply matching molecule counts, matching chromatographic response, or equivalent analytical behavior. A useful purchasing record keeps product identity and declared quantity in separate fields.

BPC-157: the expanded specification

The listed BPC-157 sequence is Gly-Glu-Pro-Pro-Pro-Gly-Lys-Pro-Ala-Asp-Asp-Ala-Gly-Leu-Val. It contains fifteen amino-acid residues and is described as a pentadecapeptide. Preserve the complete order when transcribing the specification, including the consecutive proline residues and the two adjacent aspartic acid residues. A shortened name cannot replace a full sequence in a detailed chemical record.

The molecular formula is C62H98N16O22, the listed molecular weight is 1419.5 g/mol, and the CAS identifier is 137525-51-0. These are complementary identifiers: the formula records elemental counts, the mass-per-mole value records mass per mole, and the CAS number supports catalog indexing. None should be used alone as a substitute for the complete product specification.

TB-500: the specified acetylated fragment

The listed TB-500 material is the synthetic peptide fragment Ac-LKKTETQ. The seven letters describe the residue order Leu-Lys-Lys-Thr-Glu-Thr-Gln, while Ac denotes an acetyl group at the indicated terminus. Retain that prefix when copying the name because terminal chemistry belongs to the identity description rather than optional display punctuation.

Its listed molecular formula is C38H68N10O14 and its molecular weight is 889.0 g/mol. Read these values together with Ac-LKKTETQ. The catalog name TB-500 should remain attached to this specific fragment specification; a name-only search or an unrelated document with a similar title is insufficient for confirming the contents of the supplied vial.

Equal mass is a limited comparison

Both individual vials declare 10 mg, but their different molecular weights mean equal masses correspond to different amounts in moles. For a purely theoretical comparison, dividing a mass in grams by the relevant grams-per-mole value produces moles. Such arithmetic depends on the stated chemical form and does not establish the measured peptide content of a particular lot.

Keep label amount, calculated molar amount, and analytical content in separate columns when preparing a comparison sheet. A value calculated from the catalog molecular weight remains a calculation, not a measurement. If a report describes additional chemical species or a different mass convention, resolve that information before combining its figures with a catalog-based calculation.

Why the catalog also lists a blend

The combined listing supplies BPC-157 10 mg and TB-500 10 mg together in one sealed vial. Its label describes a two-component presentation totaling 20 mg, not a single peptide with a newly combined sequence. Each component retains its own formula and molecular weight. The documented reason to distinguish this listing is its supplied composition; no additional claim about the combination follows from the component names.

Use the two component amounts when comparing the blend with the individual products. A total of 20 mg does not indicate that either component contributes 20 mg. Keep the product name and both quantities beside its lot number in receiving records so that a report for an individual material is not mistaken for a report covering the blend.

Reading analytical records

HPLC peak area describes the relative detector response assigned to a chromatographic peak under a stated method. An area percentage is not automatically a percentage of peptide content by mass. Detector response, integration choices, unresolved peaks, and sample composition all influence interpretation. Read the method and chromatogram alongside the reported number rather than treating one percentage as a complete material specification.

Mass spectrometry supplies evidence about measured ions and their mass-to-charge ratios. Agreement with an expected mass can support an identity assignment, but a matching signal alone does not establish every sequence position, distinguish all isomers, or quantify the entire vial. Review the stated ion assignment, charge state, and expected species before interpreting a mass result.

For these two distinct peptides, a chromatographic retention time is meaningful only in the context of the method used. Different columns, gradients, detectors, and integration settings can produce different records. Avoid comparing a retention time from one report with another report unless the relevant conditions are available and suitable for that comparison.

Lot matching and sealed storage

A Certificate of Analysis should match the lot printed on the vial. Confirm the product name, lot identifier, report date, and listed analytical methods before filing the document with the inventory entry. A report for another lot cannot substitute for the supplied material's record. If the identifiers differ or a field is unclear, request clarification before accepting the documentation as complete.

Keep the sealed lyophilized powder at 2–8 °C, protected from light and kept dry. Preserve the original label and maintain an inventory record that connects each vial to its lot. Record receipt date, storage location, and any observed packaging issue without opening the container merely to inspect the powder.

At receipt, compare the carton contents with the order and the label rather than relying on powder appearance. Photograph any label damage or closure concern and retain the shipment record. Cold-chain packaging describes the shipping arrangement; it does not by itself provide a continuous temperature record for every stage of transit.

A practical comparison checklist

Build the comparison around a small set of repeatable checks. Start with exact identity, then declared amount, then the lot-specific records, and finally storage and receipt details. Keeping that order prevents an attractive summary number from replacing the more basic question of whether the document actually describes the vial being reviewed.

When comparing quotations or receiving records, keep the unit beside every number. A molecular weight without g/mol can be mistaken for a vial quantity, while an amount without mg can become ambiguous after transcription. Copy identifiers directly, then review the completed entry against the label and specification. Record any correction explicitly so a later reviewer can follow the change. This modest separation of identity, units, and document status makes the comparison useful even when several peptide products share similar packaging and the same declared mass. Retain these details together for subsequent document review.

• Transcribe the complete sequence and any terminal notation.
• Record the formula, molecular weight, and declared vial amount separately.
• Match the vial lot to the COA and retain the analytical attachments.
• Log sealed storage at 2–8 °C with light and moisture protection.

Research-only scope

NF7 Research materials are supplied exclusively for in-vitro laboratory research to buyers aged 21 or older, not for human or veterinary use. Keep the product identity, lot number and applicable documentation together when reviewing a catalog specification.