What the label states, the lot delivers — net peptide mass, not gross powder weight, purity reported as measured rather than rounded up, and a Certificate of Analysis for every lot.
Net peptide mass, not powder weight; purity as measured, not rounded up; a COA per lot.
Net peptide + purity not rounded up. COA per lot.
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FDA PCAC reviews 7 peptides for the 503A bulks list in July. Read →
FDA PCAC: 7 peptides under review. Read →
Recombinant human growth hormone · 191-residue somatropin
Overview
Somatropin is recombinant human growth hormone: a 191-residue single-chain protein of roughly 22 kDa, folded with two intramolecular disulfide bonds and sequence-identical to the growth hormone the human pituitary secretes. The "191aa" tag is the identity that matters on a purchase order, it marks the natural-sequence molecule and separates it from the legacy 192-residue "somatrem" (met-hGH), which carried an extra N-terminal methionine from early direct-expression E. coli systems. Every modern recombinant hGH, Vialdyne's included, is the 191aa form. The same active ingredient underpins a long list of approved growth-hormone products, among them Genotropin, Norditropin, Humatrope, Omnitrope and Saizen. Because growth hormone is a recombinant protein rather than a synthetic peptide, its analytics differ from the rest of the catalogue and Vialdyne documents it accordingly. Each lot ships lyophilised against a ≥99.0% main-peak HPLC specification, with a batch-specific COA covering RP-HPLC peak integration, intact-mass confirmation at the ~22,124 Da theoretical, and the per-vial potency in International Units, growth hormone is value-assigned by bioactivity, so against the WHO standard of ~3 IU/mg a 10 IU vial corresponds to roughly 3.3 mg of protein. Standard fills run 6 IU to 40 IU per vial. The qualification-critical add-ons specific to a recombinant protein, the ones synthetic peptides do not need, are host-cell-protein (HCP) ELISA and bacterial endotoxin (LAL, USP <85>), with a peptide map or LC-MS/MS for sequence-level identity; Vialdyne runs these on the lot for in-vivo and compounding-track buyers. Note that recombinant hGH sits under materially heavier import and prescribing controls than the research-peptide catalogue, the regulatory note below is not boilerplate for this SKU.
Applications & buyer fit
GH-axis peptides ship to two main buyer types: compounding pharmacies dispensing under physician supervision, and research labs studying somatotropic-axis pharmacology. Pharmacies typically want sterile-filled vials with the full release packet (sterility, endotoxin, CCI); labs typically want loose-format lyophilized powder with sequence verification. Blends (the CJC-1295 / Ipamorelin combination is the canonical example) are usually co-lyophilized rather than solution-mixed for potency stability.
Sourced for
Buyer fit
Documentation that ships
Procurement note: Sterile-filled vials are available with the full release packet (sterility, endotoxin, CCI); loose lyophilized powder ships with sequence verification.
Primary buyer fit: 503A / 503B compounding pharmacies, academic and contract research laboratories, and regional distributors and re-sellers.
Specifications
Certificate of Analysis
Published released-batch COAs for HGH (Somatropin, 191aa), every lot HPLC-verified. These are previews — request the full high-resolution certificate for any lot.
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H10098 · 99.39%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H12099 · 99.30%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H15100 · 99.10%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H24101 · 99.23%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H36102 · 99.34%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H103 · 99.16%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H096 · 99.61%
VerifiedRequest full COA →HGH (Somatropin, 191aa)
VD260428-H097 · 98.87%
Regulatory note
As the active ingredient in several approved prescription growth-hormone products, somatropin is a tightly controlled recombinant hormone — considerably more regulated than research peptides. Under 21 U.S.C. §333(e), distributing growth hormone for non-approved uses is a criminal offence in the United States, while numerous other jurisdictions classify recombinant hGH as prescription-only or as a controlled substance. Where local regulation expressly permits, Vialdyne makes bulk somatropin available strictly for research and for licensed compounding, operating under the receiving party's quality system. Confirming legal eligibility to purchase, import and use recombinant hGH before ordering rests solely with the buyer.
Frequently asked questions
191aa. The material is natural-sequence somatropin, 191 residues, identical to pituitary growth hormone. The 192-residue alternative is somatrem (met-hGH), an older recombinant form carrying one extra N-terminal methionine left over when first-generation E. coli systems expressed the protein without removing the start codon's methionine; that extra residue raised immunogenicity in early clinical use, so the field standardised on the 191aa form. The COA states 191aa explicitly, treat it as a baseline identity attribute and reject any lot that cannot.
Growth hormone is dosed by bioactivity, so it is filled and labelled in International Units. Against the WHO somatropin standard of ~3 IU per milligram, the standard fills map to roughly 6 IU ≈ 2 mg, 10 IU ≈ 3.3 mg, 15 IU ≈ 5 mg, 24 IU ≈ 8 mg and 40 IU ≈ 13.3 mg. Because the IU figure reflects assayed potency rather than weighed mass, the lot COA reports per-vial IU alongside the HPLC purity and intact-mass identity.
Beyond the standard peptide packet, a recombinant protein needs controls synthetic peptides do not: (1) RP-HPLC main-peak purity at the ≥99.0% release target, (2) intact-mass confirmation against ~22,124 Da, (3) per-vial IU potency, (4) host-cell-protein (HCP) ELISA, (5) bacterial endotoxin (LAL, USP <85>), and (6) a peptide map or LC-MS/MS for sequence-level identity. HCP and endotoxin are the items most often missing from low-tier hGH documentation and the first ones a serious compounding or in-vivo buyer should insist on. Vialdyne extends the analytical scope per lot, specify destination market and intended use at quote stage.
They sit at opposite ends of the same axis, and buyers routinely weigh one against the other. Somatropin is exogenous growth hormone, the hormone itself, delivered directly. The GH secretagogues Vialdyne also lists, Sermorelin, CJC-1295 and Tesamorelin (GHRH-receptor agonists) and Ipamorelin (a GHSR/ghrelin-receptor agonist), contain no growth hormone; they prompt the recipient's own somatotrophs to release endogenous GH, which is why GHRH-plus-GHRP pairings such as CJC-1295 + Ipamorelin are run together. The practical trade-off is a defined exogenous dose that overrides physiological feedback (somatropin) versus pulsatile, self-limiting endogenous release (secretagogues). The related items below link those secretagogue SKUs for the comparison.
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