What Is the KLOW Peptide Blend? Components and Handling

The KLOW blend is a four-peptide research formulation: GHK-Cu 50 mg, TB-500 10 mg, BPC-157 10 mg and KPV 10 mg, 80 mg per vial. It is the GLOW blend with one addition, KPV, a tripeptide from alpha-MSH studied in inflammation models. Four components in one vial make concentration arithmetic and identity testing the main practical considerations.

For laboratory research use only. The compounds discussed are not approved for human or veterinary use and are not drugs, foods or cosmetics. This article summarises published research and is not medical advice.

Key points

Composition: GHK-Cu 50 + TB-500 10 + BPC-157 10 + KPV 10 mg (5:1:1:1).
KLOW = GLOW + KPV.
Blue powder and solution, from GHK-Cu.
Four distinct masses (340, 342, ~889 and 1419.5 Da) make MS identification feasible, but GHK and KPV are close in mass.
No peer-reviewed study of the four-way combination.

Components

Component	Amount	Sequence	Mass	Research context
GHK-Cu	50 mg	Gly-His-Lys + Cu(II)	340.4 Da (peptide)	Fibroblast matrix and gene-expression studies (Pickart and Margolina, 2018)
TB-500	10 mg	Ac-LKKTETQ	~889 Da	Thymosin beta-4 actin-binding region (Ho et al., 2012)
BPC-157	10 mg	GEPPPGKPADDAGLV	1419.5 Da	Tendon fibroblast migration and survival (Chang et al., 2011)
KPV	10 mg	Lys-Pro-Val	342.4 Da	PepT1-dependent NF-κB inhibition in gut cell models (Dalmasso et al., 2008)

The KLOW blend comes as a single 80 mg vial. Component profiles: GHK-Cu, TB-500, BPC-157 and KPV.

What KPV adds

KPV is the C-terminal tripeptide (residues 11–13) of α-MSH, which has long been studied for anti-inflammatory activity in experimental systems (Lipton et al., 1998). In human intestinal and immune cells, nanomolar KPV inhibited NF-κB and MAPK signalling after uptake through the PepT1 transporter, and oral KPV reduced chemically induced colitis in mice (Dalmasso et al., 2008). In KLOW, it is the only component primarily associated with inflammatory signalling rather than matrix or migration processes.

Compatibility

As in GLOW, the question is whether any component competes with GHK for copper. Copper in GHK is held by the N-terminal amine, an amide nitrogen and the histidine imidazole (Hureau et al., 2011). KPV has a free N-terminal amine but no histidine, and its proline at position 2 cannot provide an amide nitrogen for copper binding. Strong competition is therefore unlikely, though weak interactions cannot be excluded without measurement.

Reconstitution: per-component concentrations

Solvent	GHK-Cu	TB-500	BPC-157	KPV	Total
2.0 mL	25 mg/mL	5 mg/mL	5 mg/mL	5 mg/mL	40 mg/mL
3.0 mL	16.7 mg/mL	3.33 mg/mL	3.33 mg/mL	3.33 mg/mL	26.7 mg/mL
4.0 mL*	12.5 mg/mL	2.5 mg/mL	2.5 mg/mL	2.5 mg/mL	20 mg/mL

*Check vial capacity and headspace before using larger volumes. Calculate one component at a time with the peptide reconstitution calculator, and follow the general method in how to reconstitute peptides.

Testing a four-component blend

Challenge	Approach
GHK (340.4) and KPV (342.4) differ by only ~2 Da	High-resolution MS and MS/MS fragments, plus different HPLC retention
Copper may dissociate from GHK during acidic HPLC	Expect free GHK in the chromatogram; confirm copper separately if needed
Ratio verification	Calibrated HPLC peak areas for each component
Minor components (1/8 of content each)	Method sensitivity must be adequate for 10 mg in 80 mg

Storage

Store powder sealed at −20 °C, protected from light. After reconstitution, keep at 2–8 °C, avoid freeze–thaw and date the vial. The least stable of the four components limits the useful life of the solution. See how to store reconstituted peptides.

Open questions

Does KPV’s positively charged N-terminal lysine interact with the copper complex at the concentrations present in a reconstituted vial? This has not been measured.
How do four peptides of very different size and charge behave together over weeks of refrigerated storage? No stability data exist for the blend.
Is the 5:1:1:1 weight ratio based on anything other than convention? On a molar basis, the vial contains about four times more KPV molecules than BPC-157 molecules, despite equal weights.

Related research

Frequently asked questions