Pen Peptide
S23 | 50mg/1,5ml
S23 | 50mg/1,5ml
Pre-Mixed Stabilized Pen
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- 🥇 The first peptide brand with Pre-Mixed Pen stabilized formulations
- 📦 We ship with DHL Express in thermo-insulated packaging
- 💳 Secure payment by card or bank transfer
- 🧪 Purity ≥98% for precise research protocols
✅ Proper storage
✅ Proper storage
To ensure the optimal quality of our products, we pay special attention to the delivery and storage of peptides. All our shipments are sent in special cooling boxes that maintain the required temperature during transportation. This guarantees that the products will reach you in perfect condition.
After receiving the peptides, it is important to store them properly to preserve their stability and effectiveness. We recommend storing them at a temperature between 2°C and 8°C in a refrigerator. This ensures that the peptides retain their properties throughout their shelf life.
✅ Order and Delivery
✅ Order and Delivery
At Pen Peptide, we ensure fast and secure delivery of your order with DHL Express, maintaining the highest quality and reliability throughout the process.
How we process your order:
Once your payment is confirmed via bank transfer or debit/credit card, we dispatch your order on the next business day.
Orders are carefully packaged in temperature-controlled cooling boxes to ensure product integrity during transportation.
Delivery timeframe:
Standard delivery time within the Europe & UK: 1 to 3 business days (typically 1-2 business days for most locations).
Deliveries are handled exclusively by DHL Express, providing a fast and reliable shipping experience.
Tracking & order confirmation:
After your payment has been successfully processed, you will receive an email confirmation with your tracking number.
You can use the provided tracking link to monitor your shipment’s progress and estimated delivery time.
With Pen Peptide, you can trust that your order will arrive quickly and in perfect condition, ensuring a seamless and efficient experience.
✅ How does the pen work?
✅ How does the pen work?
The peptide pen is an innovative and easy-to-use device, designed for precise dosing of the substance in research settings. It is a pre-mixed pen (Pre-Mixed Pen), which means it contains an already dissolved peptide in an optimal concentration, ready for use.
Key features of the pen:
- Precision – Each pen is pre-dosed, ensuring accurate and consistent application.
- Ease of Use – No dilution or additional preparation is required.
- Sterility and Safety – Each product is manufactured in controlled laboratory conditions and sterile-packaged to guarantee its purity and effectiveness.
How to use the pen?
- Attach the needle by placing it onto the pen and twisting until fully secured.
- Set the desired dose – use the dosage dial by rotating the regulator to the corresponding number, which represents the selected units. The numbers displayed range from 0 to 60, indicating the units for dosing.
- Administer the dose according to the requirements of your research.
- Store the pen properly – in a refrigerator at a temperature between 2°C and 8°C to maintain the stability of the peptide.
With the pre-mixed pen from Pen Peptide, the process is simplified, efficient, and safe, ensuring optimal results for your research.
✅ Why choose Pen Peptide?
✅ Why choose Pen Peptide?
If you are looking for peptides of the highest quality with over 98% purity, Pen Peptide is one of the best places where you can easily and securely order online. At Pen Peptide, we specialize in the synthesis of highly purified peptides intended exclusively for Research & Development Use Only.
Our peptides are produced in certified GMP laboratories, adhering to strict standards of quality, safety, and control. Each product undergoes rigorous testing for purity and stability to ensure you receive research materials with verified origin and maximum effectiveness.
We understand how important fast and reliable service is for our customers. That’s why we offer express delivery within 1 to 3 business days. All shipments are securely packaged to maintain product quality during transportation.
✅ Molecular Structure Stabilization Process Technology (MSSPT)
✅ Molecular Structure Stabilization Process Technology (MSSPT)
The Molecular Structure Stabilization Process Technology (MSSPT) focuses on preserving the structural integrity and functionality of molecules under harsh conditions and during prolonged storage periods. This process may involve modification of the molecule itself, optimization of storage conditions, or the use of auxiliary components that protect the molecules from degradation.

Key stages of the process:
1. Molecular modification:
Chemical and genetic engineering: Involves altering the structure or composition of the molecule to make it more resistant to degradation. For example, protein cross-linking can prevent unfolding, or modification can reduce susceptibility to chemical reactions.
Chemical modification: The introduction of protective groups or changes to reactive sites can prevent unwanted chemical reactions and degradation.
2. Optimization of storage conditions:
Lyophilization (freeze-drying): This method removes water from the sample, helping to preserve structure and prevent degradation during storage.
Storage in specialized containers: Using containers that protect from light and oxygen can safeguard molecules from photodegradation or oxidation.
Controlled-release systems: These systems provide a steady concentration of the therapeutic molecule, but introduce additional challenges related to stabilizing molecules over extended release periods.
3. Use of auxiliary components:
Buffers: Buffers help maintain stable pH levels, which are crucial for many chemical reactions and biological processes.
Antioxidants: These additives can prevent or reduce oxidative degradation, which is a common cause of molecular instability.
Stabilizing agents: These help prevent aggregation, precipitation, or other forms of degradation.
4. Understanding molecular interactions:
Thermodynamic equilibrium: A fundamental understanding of the interactions between a molecule and its environment is essential for developing effective stabilization strategies.
Detergents for membrane proteins: Specialized detergents, such as those developed to stabilize membrane proteins, help maintain their structure in solution.
Molecular simulations: Techniques such as molecular dynamics can provide valuable insights into the stability and behavior of molecules.
5. Examples of stabilization techniques:
Protein stabilization: Strategies include forming disulfide bonds, using stabilizing agents or chaperones, and introducing stabilizing mutations.
Polymer stabilization: Methods include the addition of antioxidants or the use of modified clay minerals that prevent polymer degradation.
Propellant stabilization: Stabilizers are essential to prevent the decomposition of propellants and ensure their safe and reliable performance.
Pen Peptide – Proven Molecular Stabilization
Our peptide pens are developed with a strong focus on preserving the biological activity and structural stability of the active compounds. Thanks to thoroughly researched stabilization processes—including optimization of storage environments and precise modification of molecular structure—we achieve long-term durability and reliability of the peptides under appropriate storage conditions.
The MSSPT (Molecule Structure Stabilization Process Technology) we use incorporates various approaches to maintain molecular integrity, including the use of suitable buffers, antioxidants, and stabilizing agents. The MSSPT technology allows for the integration of multiple active molecules into a compact volume without compromising their structural integrity or biological effectiveness. Additional optimization of storage conditions—such as pH control and prevention of photodegradation and oxidation—ensures maximum stability and bioactivity of the peptides.
These precise measures guarantee that the final product remains effective and stable even after extended storage periods, making it a secure and reliable option for use in various research protocols.
What Is S23?
S23 is a synthetic Selective Androgen Receptor Modulator (SARM), developed to support muscle growth and fat reduction with maximum tissue selectivity. It stands out as one of the most potent compounds in its class, exhibiting exceptionally strong binding to androgen receptors and targeted action primarily in skeletal muscle tissue.
Designed for research purposes, S23 has attracted scientific interest due to its ability to maintain high levels of muscle strength and density, even under caloric restriction. It is frequently used in laboratory models focused on body recomposition, muscle recovery, and hormonal regulation.
Mechanism of Action of S23
S23 works by selectively activating androgen receptors, which play a central role in muscle growth, strength, and bone density. Upon binding to these receptors, the compound triggers cellular processes that stimulate muscle fiber development while simultaneously reducing fat mass.
Unlike traditional androgenic compounds, S23 does not convert to estrogen and does not cause water retention or unwanted growth in sensitive tissues. This makes it a relevant research target for studies seeking balanced androgenic activity with controlled effects limited to specific tissues.
Scientifically Supported Potential Benefits of S23
S23 demonstrates a range of effects that make it valuable in scientific studies related to body composition, recovery, and endocrine balance. These include:
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Significant increases in muscle mass and strength;
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Reduction in subcutaneous fat, particularly in the abdominal area;
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Maintenance of muscle density during caloric deficit;
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Enhanced muscle hardness and definition;
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Potential relevance in research related to age-related muscle loss;
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Suitable for subcutaneous application in a stabilized formula with precisely controlled dosing.
Its balanced action between anabolic potential and minimal hormonal disruption positions it as a preferred molecule for research aimed at physical optimization.
S23 vs Other SARMs
S23 is recognized as one of the most powerful SARMs, with extremely high affinity for the androgen receptor and a strong anabolic-androgenic profile. It is frequently compared with other leading compounds such as Testolone (RAD-140), Ligandrol (LGD-4033), and YK-11 due to its effectiveness in promoting muscle growth and fat loss.
Compared to RAD-140, S23 exhibits stronger androgenic potency but also a higher likelihood of suppressing endogenous testosterone. While RAD-140 offers a balance between anabolic effect and tolerability, S23 is used in studies aiming for maximal muscle stimulation and rapid body transformation, with no compromise in strength.
When compared with Ligandrol, which has a milder profile and is suited for longer research protocols, S23 is more appropriate for short, high-intensity studies where aggressive muscle building and fat burning are primary objectives. However, LGD-4033 may have an advantage in minimizing the risk of hormonal side effects.
Relative to YK-11, both compounds aim for rapid results but act through different mechanisms. S23 works through classical androgen modulation, whereas YK-11 combines androgenic activity with follistatin upregulation and myostatin inhibition. This makes YK-11 more suitable for studies targeting the enhancement of the genetic limit of muscle growth.
S23 is a powerful compound, often selected in advanced research protocols where maximum strength, muscle density, and anabolic response are sought—with the necessity of close monitoring of hormonal status.
Dosage and Application of S23 in Research Protocols
Suggested research protocol: 7 units once daily for 4–6 weeks, followed by a 2–4 week off-cycle.
1 unit = 33.33mcg
Total pen content: 150 units
Possible Side Effects of S23
Despite its high efficacy, S23 has been associated with several side effects, especially with prolonged use or elevated dosing:
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Temporary suppression of natural testosterone production depending on dose and cycle duration;
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Increased sensitivity to androgenic stimulation in certain models;
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Limited long-term data on extended use and systemic impact.
Maintaining optimal dosage and controlling application duration are critical to minimizing potential side effects.
For laboratory purposes and personal observation only.
For laboratory purposes and personal observation only.
The information has been collected from numerous studies and analyses conducted over the years and is not intended for diagnosing, treating, or preventing any diseases.
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