Hallmark Peptides Catalog
SKU HGH100-0428 · Endocrine & Growth Pathways
HGH 191aa
4.5/5 · 4 customer reviews, 4 verified purchases(service & shipping)HGH 191aa (Somatropin) is recombinant human growth hormone — a 191-amino acid single-chain polypeptide structurally identical to endogenous pituitary GH, produced via recombinant DNA technology.
Product code
HGH100-0428
Availability
In Stock · 100 units
Lyophilized peptides require laboratory reconstitution. Add Bacteriostatic Water — $4.00.
Purity money-back guarantee. If a product tests below 98% purity via an approved lab, a refund or store credit is available under our Return & Refund Policy. Opened research products are not returnable; limited returns may be approved within 5 days of delivery.
Purchase highlights
Recombinant 191-amino acid somatropin — identical to endogenous GH
Full-spectrum GH receptor binding · JAK2-STAT5 signaling · IGF-1 induction
100 IU · ≥98% purity · CAS 12629-01-5
“As a new(ish) customer, I had some troubles on my end with the way I handled the electronic payment. Even though it was my goof up, [Hallmark Peptides] still shipped out my order. It was my third order from [Hallmark Peptides]. My first two experiences were great, the peptides were great quality […], so I placed a third order - only to goof it up. Thank you for the extra care, time, communication and expense you put into that order. You have a forever customer! Thank you!”
Description
HTML contentHuman Growth Hormone (HGH) Somatropin 191aa is a recombinant form of the 191-amino acid single-chain polypeptide produced by the anterior pituitary gland. Synthesized using recombinant DNA technology, this protein is structurally identical to endogenous human growth hormone and retains full biological activity.
HGH plays a central role in linear growth, body composition regulation, glucose and lipid metabolism, bone mineralization, and organ development. Somatropin binds to the growth hormone receptor (GHR), a type I cytokine receptor present on virtually all cell types, triggering JAK2-STAT5 signaling cascades that regulate gene transcription for growth and metabolism.
Additional information
Category
Endocrine & Growth Pathways
CAS Number
12629-01-5
Availability
In stock
Delivery
10–14 business days
Coverage
United States, European Union, South America
Regulatory notice
Regulatory Compliance Notice
- Exclusively for laboratory research use
- Not intended for human or veterinary use
- Not intended for human consumption
- Not intended to diagnose, treat, cure, or prevent any disease
- Not approved by the FDA as a drug or dietary supplement
Technical Specifications
Product dataCAS Number
12629-01-5
Package Size
100 IU
Expiry
April 2028
PubChem
PubChem Substance 481150664
Storage
-20 °C (lyophilized); 2–8 °C after reconstitution
Purity
≥ 98% (HPLC)
Format
Lyophilized powder
Manufacturer
Hallmark Peptides
Warnings
Product dataResearch use only
For laboratory research use only. Not intended for human or veterinary use.
Handling
Handle with appropriate laboratory safety equipment.
Shipping & Returns
What is the delivery timeframe?
Standard shipping takes up to 14 business days after payment confirmation, depending on stock availability and logistics. Express options may be available upon request.
How are products packaged?
All peptides are shipped in temperature-controlled, discreet packaging. Products are sealed in pharmaceutical-grade vials and protected with insulated packaging to preserve integrity during transit.
What are the refund requirements?
Returns may be approved within 5 days of delivery for products that arrive damaged or with compromised seals, in their original packaging. Research-use products cannot be refunded once opened. Approved refunds are reduced by shipping and a $9.99 handling fee — see our Return & Refund Policy for full conditions.
Can an order be cancelled or refused?
Orders may be cancelled within 24 hours of placement at no charge. After that window, cancellations are subject to a 15% restocking fee. Deliveries may be refused by customs in certain jurisdictions — in such cases, a partial refund (excluding shipping) will be issued.
Customer reviews
What customers say
Reviews about our service, product quality, and shipping — published in the reviewer's own words.
Five star service!!!
As a new(ish) customer, I had some troubles on my end with the way I handled the electronic payment. Even though it was my goof up, [Hallmark Peptides] still shipped out my order. It was my third order from [Hallmark Peptides]. My first two experiences were great, the peptides were great quality […], so I placed a third order - only to goof it up. Thank you for the extra care, time, communication and expense you put into that order. You have a forever customer! Thank you!
August 2, 2026
Hallmark peptides have been nothing but great to me they are informative answered my emails back super fast concerning questions or any thing else I needed help with. Received my packages super fast I wouldn't buy from anyone else.
July 3, 2026
Product arrived on time and as expected. […] Payment needed to made via mercury payment link which was straightforward since it supports cards, wire transfer and ach
June 27, 2026
Fast shipping only thing I wasn't pleased about was having discount codes but by the time I used them and shipping fees applied it was like there was no discount at all.
May 12, 2026
Reviews are collected from customers with real orders and published without compensation, newest first. “Verified purchase” is assigned by matching the reviewer to an order number. In line with our research-use policy, passages describing product use are removed and marked “[…]”. “[Hallmark Peptides]” in brackets marks where a reviewer wrote our former brand name, Blue Ridge. The featured quote near the price is selected from 5-star reviews.
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