YK-11 (Myostine)

Description

Pure Rawz YK-11 is a steroidal androgen receptor partial agonist, available as capsules, tablets, a liquid, a powder, an injectable solution and a transdermal liquid. Every batch is tested for 99% purity or better, and it’s sold for laboratory research only.

What is YK-11?

YK-11 is a steroidal compound built on a dihydrotestosterone backbone, first described by Japanese researchers in 2011. It’s usually sold next to SARMs, but it’s a steroid and only a partial agonist at the androgen receptor.

Its reported trait is raising follistatin in muscle cells, which ties it to myostatin research.

How it works

YK-11 binds the androgen receptor but doesn’t trigger the full shape change that DHT does, so it activates only part of the usual gene program. That’s why it’s called a partial agonist.

In muscle cells it raised follistatin, a protein that blocks myostatin, the signal that limits muscle growth. When the researchers blocked follistatin, YK-11’s effect on muscle cell differentiation went away.

What studies say about YK-11

Kanno and colleagues showed in Biological and Pharmaceutical Bulletin in 2013 that YK-11 drove muscle cell differentiation in C2C12 myoblasts more strongly than DHT and raised follistatin expression.

A 2018 study reported effects on bone-forming osteoblast cells as well. There are no human trials.

For the studies themselves, try this PubMed search.

YK-11 sizes and forms

Choose the option that fits your study:

• Capsules, 10mg/60ct/600mg: $174.05
• Tablets, 6mg/50ct/300mg: $87.02
• Tablets, 6mg/100ct/600mg: $174.05
• Liquid, 15ml/17mg per ml/250mg: $72.52
• Liquid, 30ml/17mg per ml/500mg: $145.04
• Liquid, 30ml/33mg per ml/1000mg: $290.09
• Powder, 1g: $290.09
• Injectable, 10ml/64mg per ml = 640mg: $185.66
• Transdermal, 60ml/17mg per ml/1000mg: $290.09

Capsules hold a measured amount each, listed in the size option with the count and total.

Tablets are pressed with a fixed amount per tablet, shown in the size option along with the count.

The liquid comes in a glass dropper bottle at a stated concentration per mL, so every draw is easy to calculate.

The powder is the bulk form, for labs that weigh their own amounts. Use a milligram scale for accuracy.

The injectable form is a sterile solution in a sealed vial at a stated concentration per mL.

Transdermal bottles hold a solution built for skin application studies, with the concentration on the label.

How labs use it

Labs comparing SARMs usually match exposure time and measure the same panel across compounds: muscle and prostate weight in rodents, plus hormone and lipid markers. That tissue-selectivity ratio is what SARM research is built around.

Liquids make small, even measurements easy, while capsules and tablets suit studies that need a fixed amount per unit.

Run a baseline panel before exposure starts. Without it, hormone changes are hard to interpret.

Measuring the liquid

At 17mg per mL, every 1mL holds 17mg and every 0.1mL holds 1.7mg. A graduated 1mL dropper or syringe makes those measures accurate.

YK-11 at a glance

• Compound: YK-11
• Also known as: YK11
• CAS number: 1370003-76-1
• Molecular formula: C25H34O6
• Molar mass: 430.5 g/mol
• Structure: steroidal (DHT-derived) structure
• Class: steroidal androgen receptor partial agonist
• Forms: capsules, tablets, liquid, powder, injectable and transdermal
• Options: 9 sizes and forms
• Purity: 99% or higher, verified by first- and third-party testing
• Use: laboratory research only

Quality and testing

We test each batch for identity and purity before it ships, using HPLC and mass spectrometry, with independent third-party checks on top of our own.

The batch number on the label matches the certificate of analysis. If your lab keeps paperwork on file, ask us for it and we’ll email it over.

Storage and shelf life

Store capsules, tablets and powder in a cool, dry place out of direct light, with the lid closed tight. Keep the bottle capped, upright and out of direct sunlight at room temperature unless the label says otherwise.

Label the container with the opening date. It saves guesswork later.

Working with it safely

Handle it the way you’d handle any research chemical: gloves, eye protection and a clean bench. Don’t eat or drink where you work with it.

Keep it out of reach of anyone who isn’t trained, and dispose of used syringes, vials and wipes according to your lab’s waste rules.

Before you start

• a graduated 1mL dropper or syringe for accurate volumes
• a milligram scale, since powder has to be weighed
• a suitable solvent if you’re making your own solution, such as DMSO or propylene glycol

Often ordered alongside

• S-23 MK-677 Combined Formula: The S-23 MK-677 Combined Formula puts 10mg of S-23 and 10mg of MK-677 in each capsule, 20mg per capsule and 60 capsules.
• RAD-140 + MK-677 + YK-11 Value Pack, combining RAD-140, MK-677 and YK-11
• RAD-140 + S-23 Injectable, combining RAD-140 and S-23
• Extreme Cycle Capsules: Extreme Cycle is a 120-capsule formula (four capsules per serving) of TUDCA (350mg), L-tyrosine (410mg), NAC (410mg), green tea leaf (220mg), acetyl L-carnitine (110mg), alpha lipoic acid (110mg), grape seed extract (65mg) and zinc.
• S23 + S4 + GW-501516 Value Pack, combining S-23, S4 Andarine and GW501516

See the rest of our SARMs for more options.

YK-11 FAQ

Can it be used in people or animals?

No. It’s sold for laboratory research only and isn’t approved for human or veterinary use.

How should I store it?

Follow the storage section above. In short: cold and dark for freeze-dried vials, room temperature and dry for capsules, tablets, powders and liquids, unless the label says otherwise.

What forms does it come in?

Capsules, tablets, a liquid, a powder, an injectable solution and a transdermal liquid. Pick the one you want from the dropdown on this page.

Is YK-11 in stock?

Yes. It’s in stock and ships from our warehouse after your order clears.

Does it come with a certificate of analysis?

Yes. Every batch is tested, and we’ll email the certificate of analysis for your batch number on request.

Order YK-11 today

YK-11 is in stock from $72.52. Choose your option, add it to the cart and check out in a couple of minutes.

Need more for the same project? Have a look at our SARMs.

For laboratory research use only. Not for human or veterinary use. These statements have not been evaluated by the FDA.