KLOW Blend Pen
GHK-Cu 150 mg with BPC-157, TB-500 (thymosin beta-4) and KPV at 30 mg each, dissolved in 3 mL of bacteriostatic water at 80 mg/mL. Filled from peptide tested in the manufacturer’s own laboratory, with a certificate.
| Components | GHK-Cu (Copper tripeptide-1; Gly-His-Lys · Cu(II))BPC-157 (Body Protection Compound-157; pentadecapeptide)TB-500 (Thymosin β4); N-acetyl thymosin β4, full-length 43-residue peptideKPV (Lys-Pro-Val; α-MSH(11–13)) |
|---|---|
| GHK-Cu CAS number | 89030-95-5 |
| BPC-157 CAS number | 137525-51-0 |
| TB-500 (Thymosin β4) CAS number | 77591-33-4 |
| KPV CAS number | 67727-97-3 |
| Contents | GHK-Cu: 150 mg per 3 mL pen (5% w/v)BPC-157: 30 mg per 3 mL pen (1% w/v)TB-500 (Thymosin β4): 30 mg per 3 mL pen (1% w/v)KPV: 30 mg per 3 mL pen (1% w/v) |
| Form | Sterile aqueous solution in bacteriostatic water (0.9% benzyl alcohol), supplied in a 3 mL glass cartridge inside a preloaded autoinjector pen fitted with a needle |
| Storage, sealed | Store at 2–8 °C in the original carton, protected from light |
| Format | Solution in a 3 mL pre-filled pen |
Sizes and lots
- 240 mg · 1 pen — $198.99
- 240 mg · Kit of 10 — $1912.99
Each of the four has its own research literature, on matrix repair, blood vessel growth, actin and inflammation. None of that work tested the four together, in a pen or in any other form.
What is in the KLOW pen
The safety data sheet for the KLOW peptide pen gives the contents of each 3 mL cartridge: GHK-Cu 150 mg (5% w/v), with BPC-157, TB-500 and KPV at 30 mg each (1% w/v). That is 240 mg of peptide, or 80 mg/mL, in the same 5:1:1:1 mass ratio as the 80 mg vial. The solvent is bacteriostatic water containing 0.9% benzyl alcohol, which the sheet classifies as harmful if swallowed or inhaled, an eye irritant and a possible skin sensitiser; none of the four peptides is classified. The copper complex makes the solution clear blue to blue-violet.
Keep the pen in its carton at 2 to 8 °C, away from light and capped between uses, and never let it freeze. Discard it if the solution has frozen, changed colour or turned cloudy. The freeze-dried KLOW Blend 80 mg vial holds the same four peptides for work that needs its own concentration.
What the research covers
The pen's four components come from unrelated research areas. GHK-Cu is a copper-binding plasma peptide that a 2018 review credits with stimulating collagen, elastin and glycosaminoglycan synthesis and the outgrowth of blood vessels and nerves, and with tissue repair in skin, lung connective tissue, bone, liver and stomach lining1. Thymosin beta-4, the full-length molecule sold here as TB-500, binds actin and promotes cell migration; a 2012 review described it as released by platelets and macrophages after injury and as lowering myofibroblast numbers and scarring in wounds2. The clinical trials that review mentions were ongoing or planned, and it reports no outcomes2. KPV, a three-residue fragment of alpha-MSH, blocked NF-κB and MAP kinase signalling at nanomolar concentrations in human intestinal and T cell lines3. The rat and cell studies on BPC-157 are summarised on the KLOW Blend 80 mg vial page.
What a four-peptide COA has to cover
A single-compound certificate answers two questions, identity and purity. A four-component blend needs more than that, and the extra questions are the ones most worth asking a supplier about any KLOW blend peptide lot. Each research peptide in the blend is a separate analytical problem.
Identity and purity have to be reported per component rather than once for the mixture, because a single chromatogram covering four peptides at a 5:1:1:1 ratio will not resolve the impurity profile of the three minor ones cleanly. The ratio itself is the second question: a stated 80 mg/mL total says nothing about how that mass divides, and the ratio is the one figure a purchaser cannot work out from the outside. Three of the four components have no aromatic residue worth detecting at 280 nm, so purity has to be read at 214 nm with the gradient stated, and the copper complex adds its own absorbance that has to be accounted for rather than ignored.
A bacterial endotoxin result belongs on the list for any aqueous product and is the field most often absent. It is not reported by a purity percentage: bacterial cell-wall fragments can be present in chemically pure material, and an LAL result on the specific lot is the only thing that addresses it. For anything bought elsewhere, a COA without that line has not answered the question, and an analysis of 6,441 grey-market peptide samples found measurable endotoxin in 15 per cent of them, with between 41.6 and 71.1 per cent failing basic quality criteria depending on framework4. That paper is a preprint and has not completed peer review, so read the figures as indicative.
Format decides what a buyer can still check after delivery. A KLOW vial of lyophilized powder can be weighed, split and sent out for independent analysis on material the researcher controls, and the reconstitution volume sets the concentration in the laboratory rather than at the factory. Prefilled peptide pens remove the weighing and the reconstitution step and fix the concentration, and in exchange every identity and purity question resolves to a measurement taken at the fill. That is the real trade in the format, and it applies to all prefilled peptide pens rather than to this research peptide in particular. A lot-specific certificate of analysis is the document to ask for in either case; a representative certificate of analysis describes a batch nobody can now locate.
KLOW, GLOW, and what peptide synergy would have to show
A KLOW blend peptide listing is four research peptides in one container, and the blends in this range differ by one component with the naming recording it. The KLOW blend pen holds GHK-Cu, BPC-157, thymosin beta-4 and KPV. The GLOW blend is the same arrangement without the KPV, so GHK-Cu, BPC-157 and thymosin beta-4, and a GKP blend drops the thymosin instead. Each is sold as a repair blend, and the KLOW peptide pen is the four-component version of that idea at 80 mg/mL.
Peptide synergy is the claim the naming implies, and it has a specific evidentiary meaning: a combined effect larger than the sum of the components measured separately. Showing it requires a factorial experiment: each peptide alone, the combination, and a control, with an endpoint measured the same way across all arms. No such experiment has been published for these four, for any three of them, or for any pair except BPC-157 with thymosin beta-4 in a single rat tendon study. So synergy here is a hypothesis about the KLOW blend peptide mixture rather than a finding, and the component literature summarised above cannot settle it in either direction.
The same applies to the headings the blend is searched under. Tissue repair is the umbrella for the GHK-Cu and thymosin beta-4 work, both of which report tissue repair endpoints in animals and in cell culture rather than in people. Cellular repair is a looser phrase with no endpoint attached to it anywhere in this file. Anti-inflammatory signaling is the accurate description of what the KPV work measured, since blocking NF-kB and MAP kinase signalling in cultured intestinal and T cell lines is a signalling result rather than a clinical anti-inflammatory one. MOTS-c appears beside these products in catalogues and belongs to none of this: it is a sixteen-residue peptide encoded in mitochondrial DNA and studied for metabolic endpoints, with no connection to the four components here.
Frequently asked questions
How is the KLOW pen different from the KLOW vial?
The vial holds 80 mg of the four peptides as freeze-dried powder, stored at −20 °C and dissolved in the lab. The KLOW pen holds 240 mg of the same four, already dissolved at 80 mg/mL in bacteriostatic water and kept at 2 to 8 °C. The 5:1:1:1 mass ratio is the same in both.
Has anyone studied these four peptides together in solution?
No published study has. Each component has its own literature, but nothing has been reported on the four combined: not their stability in one solution, not any interaction with the copper complex, and not any combined biological effect.
What should a COA show for a four-peptide blend?
Identity and purity per component rather than once for the mixture, the ratio between the four, purity at 214 nm with the gradient stated since three of the four have no useful absorbance at 280 nm, and an endotoxin result on the specific lot. A stated 80 mg/mL total says nothing about how the mass divides, and that ratio is the figure a purchaser cannot determine from outside.
Why does endotoxin need its own line?
Because a purity percentage does not report it. Bacterial cell-wall fragments can be present in chemically pure material, so an LAL result on the lot is the only thing that addresses it. An analysis of 6,441 grey-market peptide samples found measurable endotoxin in 15 per cent, with 41.6 to 71.1 per cent failing basic quality criteria depending on framework4; that paper is a preprint and has not completed peer review.
How does KLOW differ from GLOW?
By one component. The KLOW blend pen holds GHK-Cu, BPC-157, thymosin beta-4 and KPV; the GLOW blend is the same without the KPV. A GKP blend drops the thymosin instead. All three are sold as a repair blend, and the KLOW peptide pen is the four-component version at 80 mg/mL.
Has peptide synergy been demonstrated for these four?
No. Synergy means a combined effect larger than the sum of the components measured separately, which needs a factorial experiment: each peptide alone, the combination and a control, with one endpoint measured the same way throughout. No such study exists for these four, for any three, or for any pair other than BPC-157 with thymosin beta-4 in one rat tendon experiment.
Is MOTS-c part of this blend or related to it?
Neither. MOTS-c is a sixteen-residue peptide encoded in mitochondrial DNA, studied for metabolic endpoints, and it appears beside these products in catalogues rather than in their literature. None of the four components here has any connection to it.
References
- Pickart L, Margolina A. Regenerative and Protective Actions of the GHK-Cu Peptide in the Light of the New Gene Data. Int J Mol Sci. 2018;19(7). DOI · PubMed
- Goldstein AL, Hannappel E, Sosne G, et al. Thymosin β4: a multi-functional regenerative peptide. Basic properties and clinical applications. Expert Opin Biol Ther. 2012;12(1):37-51. DOI · PubMed
- Dalmasso G, Charrier-Hisamuddin L, Nguyen HT, et al. PepT1-mediated tripeptide KPV uptake reduces intestinal inflammation. Gastroenterology. 2008;134(1):166-78. DOI · PubMed
- Mendias CL, Awan TM. Quality analysis of grey-market peptide samples. Preprint, not peer reviewed. DOI
For laboratory research use only. Not for human or veterinary consumption. Products have not been evaluated by the U.S. Food and Drug Administration and are not intended to diagnose, treat, cure or prevent any disease.