GLOW vs KLOW Peptide Blends: What’s the Difference?
GLOW and KLOW are two of the most popular multi-peptide research blends, and their names cause a lot of confusion. They share three ingredients but are built for different research questions. This guide breaks down what is in each blend, what each component is studied for, and how to choose between GLOW50, GLOW70, KLOW and KLOW70.
What’s in each blend
| Component | GLOW50 / GLOW70 | KLOW | KLOW70 |
|---|---|---|---|
| GHK-Cu | ✓ | ✓ | ✓ |
| BPC-157 | ✓ | ✓ | ✓ |
| TB-500 | ✓ | ✓ | — |
| KPV | — | ✓ | ✓ |
| Larazotide | — | ✓ | ✓ |
The simplest way to remember it: GLOW is the core repair trio. KLOW adds two peptides aimed at inflammation and the epithelial barrier. KLOW70 is KLOW without TB-500.
What each component is studied for
- GHK-Cu: a copper-binding tripeptide studied for collagen and extracellular-matrix synthesis and tissue remodeling in fibroblast models.
- BPC-157: a 15-amino-acid peptide studied for angiogenesis, nitric oxide signaling and fibroblast and tendon-cell migration.
- TB-500: based on thymosin beta-4, studied for actin regulation, cell migration and wound closure.
- KPV: the anti-inflammatory C-terminal tripeptide of α-MSH, studied in NF-κB signaling and intestinal epithelial models.
- Larazotide: a peptide studied for its effects on epithelial tight junctions, the seals between cells that control intestinal barrier permeability. See larazotide explained.
GLOW: matrix, angiogenesis and migration
GLOW combines the copper-peptide matrix signaling of GHK-Cu with the two classic repair peptides. It is used in dermal fibroblast, wound-closure and extracellular-matrix models, where researchers want collagen-pathway effects alongside angiogenesis and cell migration in one consistent vial.
GLOW50 vs GLOW70: same three peptides, different total mass (50 mg vs 70 mg). GLOW70 suits larger studies, or keeping a longer study on a single lot to avoid lot-to-lot variation.
KLOW: adding inflammation and barrier pathways
KLOW keeps the GLOW trio and adds KPV and Larazotide. The extra components extend the blend into inflammatory signaling and tight-junction biology, which makes it the more common choice for gut-barrier and epithelial repair models, where inflammation, barrier integrity and tissue repair interact.
KLOW70: KLOW without TB-500
KLOW70 removes TB-500 and keeps KPV, Larazotide, GHK-Cu and BPC-157. Running KLOW and KLOW70 side by side lets researchers isolate what TB-500’s effects on actin and cell migration contribute in a multi-peptide model.
How to choose
Dermal, fibroblast or matrix-remodeling models: GLOW50 or GLOW70.
Gut-barrier, epithelial or inflammation-linked repair models: KLOW.
Isolating TB-500’s role in a KLOW-type model: KLOW70 next to KLOW.
Separating every component’s effect: run the single peptides alongside the blend. GHK-Cu, BPC-157, TB-500 and KPV are all available individually.
Why blends need careful testing
With several peptides in one vial, a single purity figure is not enough. Each component should be confirmed. Every blend lot we sell is tested by Bioviridian Labs (ISO/IEC 17025, Texas) for HPLC purity, mass-spectrometry identity, endotoxin and heavy metals. Read what HPLC purity measures, and check any lot in the COA Library.
For laboratory research use only. Not for human or veterinary use. This article summarizes published research for educational purposes and does not provide medical advice.