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HGH Fragment 176-191

Name: HGH Fragment 176-191
Brand: PeptideXpo
SKU: hgh-fragment-176-191

C-terminal fragment of human growth hormone (176–191)

≥ 99.0%CAS 66004-57-7GH-Axis Peptides

PeptideXpo buyer fit

HGH Fragment 176-191 for distributor assortment and OEM sourcing comparison

This PeptideXpo page is intentionally positioned for distributors, OEM buyers, and procurement teams comparing HGH Fragment 176-191 inside a wider peptide catalog. It is not trying to be the deepest single-molecule monograph; the differentiated intent is assortment planning, export-ready documentation, fill-size comparison, and whether this SKU belongs in a broader buyer program.

Use this page when the buyer is comparing multiple SKUs, fill ladders, repeat-order economics, or distributor/OEM sourcing routes.
For regulated compounding-pharmacy qualification, a dedicated regulated-pharmacy channel should own the pharmacy-specific head keyword.
For research-lab method development, copper-chemistry, or cosmetic-formulation depth, the matching specialist channel (research standards, copper peptides, or cosmetic actives) should own the narrower specialist intent.

Overview

HGH Fragment 176-191 is the unmodified 16-amino-acid C-terminal fragment of native human growth hormone, corresponding to residues 176-191 of the full-length 191-amino-acid HGH protein. The fragment retains the lipolytic activity associated with this region of native HGH while lacking the central regions that mediate the broader anabolic and IGF-1-stimulating effects of full-length GH. Distinct from the AOD9604 modified analog (which adds an N-terminal tyrosine for iodination-tracking purposes), HGH Fragment 176-191 is the unmodified native sequence and is the form typically used in research workflows studying the lipolytic activity of the HGH C-terminal region in isolation from the rest of the molecule. PeptideXpo supplies HGH Fragment 176-191 at ≥99.0% HPLC purity with full identification: CAS 66004-57-7, formula C78H123N23O22S2, MW 1799.1 g/mol, sequence FLRIVQCRSVEGSCGF (note the two cysteines at positions 7 and 14 that can form an intramolecular disulfide bridge under oxidative conditions). The disulfide-bridging behavior is the most common identity-confirmation concern, the reduced and oxidized forms differ by 2 Da and elute at different RP-HPLC retention times. Six standard fill sizes (1-15 mg) cover most research and compounding workflows.

Who buys this, and why

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 bulk 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.

Primary buyer fit: academic and contract research laboratories and 503A / 503B compounding pharmacies.

Specifications

CAS: 66004-57-7
Molecular Formula: C78H123N23O22S2
Molecular Weight: 1799.1 g/mol
Sequence: FLRIVQCRSVEGSCGF
Appearance: White to off-white lyophilized powder
Purity (HPLC): ≥ 99.0%
Strength: 1 mg – 15 mg
Packaging: 10 vials/box · base pack (multiples of 10)
Half-life: ≈ 30-40 minutes
MOQ: On request
Lead time: 10–18 days
Storage: -20°C, protect from light

Documentation available on request

Certificate of Analysis (COA)
HPLC Chromatogram
Mass-spec identity (ESI-MS)
Counter-ion (acetate vs TFA)
Sterile-fill release pack (sterility, CCI, fill-weight)
Bacterial endotoxin (LAL, USP <85>)
Stability data on request
SDS / MSDS

Regulatory note

Easily confused with AOD9604 (the modified analog with N-terminal tyrosine). Confirm exact fragment identity (unmodified vs. AOD9604-modified) via batch COA before order placement; the two are not chemically equivalent.

Selected literature

Ng FM, Bornstein J. Hyperglycemic action of synthetic C-terminal fragments of human growth hormone. Am J Physiol. 1978;234(5):E521-E526.
Heffernan MA, Jiang WJ, Thorburn AW, Ng FM. Effects of oral administration of a synthetic fragment of human growth hormone on lipid metabolism. Am J Physiol Endocrinol Metab. 2000;279(3):E501-E507.
Heffernan M, Summers RJ, Thorburn A, Ogru E, Gianello R, Jiang WJ, Ng FM. The effects of human GH and its lipolytic fragment (AOD9604) on lipid metabolism following chronic treatment in obese mice and beta3-AR knock-out mice. Endocrinology. 2001;142(12):5182-5189.
Heffernan MA, Thorburn AW, Fam B, Summers R, Conway-Campbell B, Waters MJ, Ng FM. Increase of fat oxidation and weight loss in obese mice caused by chronic treatment with human growth hormone or a modified C-terminal fragment. Int J Obes Relat Metab Disord. 2001;25(10):1442-1449.
Stier H, Vos E, Kenley D. Safety and tolerability of the hexadecapeptide AOD9604 in humans. J Endocrinol Metab. 2013;3(1-2):7-15.
More MI, Kenley D. Safety and metabolism of AOD9604, a novel nutraceutical ingredient for improved metabolic health. J Endocrinol Metab. 2014;4(3):64-77.

Frequently asked questions

How do I distinguish HGH Fragment 176-191 from AOD9604 at the analytical level?▾

The two molecules differ at the N-terminal residue: AOD9604 is Tyr-hGH(177-191) — an N-terminal tyrosine on residues 177-191, a 16-amino-acid molecule with theoretical MW ≈1815 Da — while HGH Fragment 176-191 is the unmodified native 16-amino-acid sequence (phenylalanine at position 176) at theoretical MW ≈1799 Da. The ≈16 Da mass difference (Phe→Tyr adds one oxygen) is the diagnostic mass-spec check at first-time supplier qualification. The two forms also resolve at slightly different RP-HPLC retention times under typical conditions. Buyers should always confirm the released-batch mass against the expected mass for the form they ordered, since the molecules are easy to confuse but biologically distinct.

What does the intramolecular disulfide bond in HGH Fragment 176-191 mean for handling?▾

The 176-191 sequence (FLRIVQCRSVEGSCGF) contains two cysteines (positions 7 and 14 within the fragment) that can form an intramolecular disulfide bond. Under reducing conditions during synthesis, the cysteines are free thiols; under oxidative conditions during storage and reconstitution, they can form the disulfide bridge. The reduced and oxidized forms differ by 2 Da in mass and elute at different RP-HPLC retention times. Most published research uses the oxidized (disulfide-bridged) form, which is the more stable solid-state form. Buyers should confirm with the COA which form the batch represents, if your research protocol requires a specific form, this matters operationally.

Related peptides

Buyers who view HGH Fragment 176-191 also ask about:

AOD9604

≥99.0%

Modified HGH fragment 176–191 (anti-obesity drug candidate)

CAS: 221231-10-3
Vial: 2 mg–10 mg

MOQ on requestGet quote →

29-mer

Sermorelin

≥99.0%

GHRH 1-29 fragment

CAS: 86168-78-7
Vial: 2 mg–10 mg

MOQ on requestGet quote →

See full catalog

HGH Fragment 176-191

C-terminal fragment of human growth hormone (176–191)

≥ 99.0%CAS 66004-57-7GH-Axis Peptides

PeptideXpo buyer fit

HGH Fragment 176-191 for distributor assortment and OEM sourcing comparison

Use this page when the buyer is comparing multiple SKUs, fill ladders, repeat-order economics, or distributor/OEM sourcing routes.
For regulated compounding-pharmacy qualification, a dedicated regulated-pharmacy channel should own the pharmacy-specific head keyword.
For research-lab method development, copper-chemistry, or cosmetic-formulation depth, the matching specialist channel (research standards, copper peptides, or cosmetic actives) should own the narrower specialist intent.

Overview

Who buys this, and why

Primary buyer fit: academic and contract research laboratories and 503A / 503B compounding pharmacies.

Specifications

CAS: 66004-57-7
Molecular Formula: C78H123N23O22S2
Molecular Weight: 1799.1 g/mol
Sequence: FLRIVQCRSVEGSCGF
Appearance: White to off-white lyophilized powder
Purity (HPLC): ≥ 99.0%
Strength: 1 mg – 15 mg
Packaging: 10 vials/box · base pack (multiples of 10)
Half-life: ≈ 30-40 minutes
MOQ: On request
Lead time: 10–18 days
Storage: -20°C, protect from light

Documentation available on request

Certificate of Analysis (COA)
HPLC Chromatogram
Mass-spec identity (ESI-MS)
Counter-ion (acetate vs TFA)
Sterile-fill release pack (sterility, CCI, fill-weight)
Bacterial endotoxin (LAL, USP <85>)
Stability data on request
SDS / MSDS

Regulatory note

Selected literature

Ng FM, Bornstein J. Hyperglycemic action of synthetic C-terminal fragments of human growth hormone. Am J Physiol. 1978;234(5):E521-E526.
Heffernan MA, Jiang WJ, Thorburn AW, Ng FM. Effects of oral administration of a synthetic fragment of human growth hormone on lipid metabolism. Am J Physiol Endocrinol Metab. 2000;279(3):E501-E507.
Heffernan M, Summers RJ, Thorburn A, Ogru E, Gianello R, Jiang WJ, Ng FM. The effects of human GH and its lipolytic fragment (AOD9604) on lipid metabolism following chronic treatment in obese mice and beta3-AR knock-out mice. Endocrinology. 2001;142(12):5182-5189.
Heffernan MA, Thorburn AW, Fam B, Summers R, Conway-Campbell B, Waters MJ, Ng FM. Increase of fat oxidation and weight loss in obese mice caused by chronic treatment with human growth hormone or a modified C-terminal fragment. Int J Obes Relat Metab Disord. 2001;25(10):1442-1449.
Stier H, Vos E, Kenley D. Safety and tolerability of the hexadecapeptide AOD9604 in humans. J Endocrinol Metab. 2013;3(1-2):7-15.
More MI, Kenley D. Safety and metabolism of AOD9604, a novel nutraceutical ingredient for improved metabolic health. J Endocrinol Metab. 2014;4(3):64-77.

Frequently asked questions

How do I distinguish HGH Fragment 176-191 from AOD9604 at the analytical level?▾

What does the intramolecular disulfide bond in HGH Fragment 176-191 mean for handling?▾

Related peptides

Buyers who view HGH Fragment 176-191 also ask about:

AOD9604

≥99.0%

Modified HGH fragment 176–191 (anti-obesity drug candidate)

CAS: 221231-10-3
Vial: 2 mg–10 mg

MOQ on requestGet quote →

29-mer

Sermorelin

≥99.0%

GHRH 1-29 fragment

CAS: 86168-78-7
Vial: 2 mg–10 mg

MOQ on requestGet quote →

See full catalog