Snowman Research · Nov 11, 2026

Yiwu Ranbu & Irene Yang Sold Us Fake Retatrutide: A Global Sources Peptides Warning (+852 5509 8176)

Why we are publishing this

This is an embarrassing post for us to write. But faketides are on the rise in 2026, and this is a lesson we would rather people read about than learn for themselves. We also want to find the source of these faketides. Whoever made the vials, the seller we bought them from, Irene Yang of Yiwu Ranbu E-commerce Co., Ltd, is at the very least connected to that supply chain.

Buying peptides on Global Sources? Read this first

Yiwu Ranbu E-commerce Co., Ltd and its sales rep Irene Yang (WhatsApp +852 5509 8176) sold us retatrutide in which an independent lab could not detect any retatrutide. We found them on Global Sources, a large B2B marketplace many buyers use to find a peptide supplier, and they carry a "Verified" badge there. A badge is not a lab result. If you are thinking about buying peptides on Global Sources, this is a Global Sources peptide supplier you should know about: here is exactly what we saw, the proof, and how to test any Global Sources retatrutide or other vial yourself before you pay for more. Short version of our Yiwu Ranbu review: it failed, and the company's answer was an offer tied to buying more.

Part 1: What happened with Irene Yang and Yiwu Ranbu E-commerce Co., Ltd

Who they are on Global Sources

We found Irene Yang and Yiwu Ranbu E-commerce Co., Ltd on Global Sources. Their supplier page shows a Standard supplier badge and a "Verified" tag. It also says their products go through "advanced laboratories and strict quality control" and are "safe and effective." Those are their claims. Here is what we found when we checked.

Irene Yang moves the conversation to WhatsApp

When we contacted the company on Global Sources, the reply came from Irene Yang. It invited us to move to WhatsApp at +852 55098176. Global Sources itself tells buyers to keep conversations on its platform.

We bought their Retatrutide 30mg, then tested it

We bought Retatrutide from Irene Yang's company. Before relying on it, we sent a vial of the Retatrutide 30mg to an independent lab, Janoshik Analytical, for testing.

Janoshik's report (task #250495, batch RT30306261A) asked a simple question: is a common GLP-1 peptide (semaglutide, tirzepatide or retatrutide) in this vial? The answer:

In plain terms: Janoshik found no retatrutide in the vial we sent. Anyone can check the report on Janoshik's own site: verify.janoshik.com, key VKVA7G3FNMP6.

We asked the lab what it actually found

A "not detected" line leaves a question open: what is in the vial instead? We asked Janoshik directly. This is the exchange, in their words and ours.

Our email to Janoshik · Nov 10, 2026, 12:19 PM CT

"The result came back 'Common GLP-1 peptide: not detected' with no comments, and I'd like to understand what you saw. ... Was there a peak consistent with a filler or excipient (such as mannitol), an unidentified peak, or essentially nothing at all?"

Janoshik customer care reply · Nov 11, 2026, 7:40 AM CT

"Our analytical team has examined the sample and confirmed that the only substance they were able to identify was mannitol."

Mannitol is a common bulking agent in freeze-dried (lyophilized) products, so it is not unusual by itself. What matters is what the lab did not report: retatrutide.

We pulled it from sale

On Nov 10, 2026, right after the result, we took Retatrutide 30mg off sale. We also pulled all of their products, not just this one, and replaced them with stock from other suppliers. We would rather lose a product than sell one we cannot stand behind.

The company's response

We contacted Yiwu Ranbu through Global Sources with the lab link. In that message we asked them to confirm whether Irene Yang represents their company, and to refund or replace the order with verified product.

Our Global Sources inquiry to Yiwu Ranbu E-commerce Co.,LTD

"To the management of Yiwu Ranbu E-commerce Co.,LTD: Your sales rep Irene Yang (WhatsApp +852 55098176), who contacted me through your Global Sources page ... An independent Janoshik Analytical lab test found NO GLP-1 peptide in the RT30: [verify link] ... Please confirm whether she represents your company and refund [the amount] or replace the order with verified product within 7 days."

Irene's answer, over WhatsApp: no refund and no replacement for the product that failed testing. Her message said the company would ship "the rest" in batches, with extra boxes added with each new order placed. In other words, nothing ships unless we place new orders. We replied that we wanted the order we already paid for reshipped as real product, so we could test it before placing any new order. We held back our fraud report to Global Sources briefly to give the company a chance to respond. Nothing was offered to make the failed product right, only an incentive to buy more.

Let's call this what it is: fraud. They took our money for retatrutide, delivered vials with no retatrutide in them, and when the lab proved it, the only offer was to send more product if we paid for new orders. That is not customer service. That is a fraudster trying to get paid twice. We still expect a full refund, and we will update this post if one ever arrives.

Treat any vendor's product quality guarantee like someone offering to sell you a bridge. "Lab tested," "99% purity," "safe and effective" and "Verified" are just words. Even a vendor's own lab report proves little, because the vendor chooses which vial goes to the lab and controls the caps, labels and batch codes. The only result you can really trust is one from a vial you bought yourself and tested at home or sent to a lab yourself. And when something does go wrong, the product quality guarantee is usually the first thing to go sideways. Ours did: once the test failed, the quality guarantee turned into excuses and an offer of free boxes on a new order, with no refund.

Our advice

Do not buy from Irene Yang or Yiwu Ranbu E-commerce Co., Ltd (Global Sources, WhatsApp +852 5509 8176). In our experience they are fraudsters selling faketides. The Janoshik result applies to the vial we sent. If Irene Yang or Yiwu Ranbu has independent test results for this batch or wishes to respond, email [email protected] and we will add it to this post.

Is Yiwu Ranbu a scam? Yes. Here is the evidence

In our experience, yes. Yiwu Ranbu and Irene Yang sold us fake retatrutide and refused to make it right. Every item below is documented, and you can check it yourself:

• Lab result: Janoshik Analytical report #250495 on the Retatrutide 30mg from Ranbu E-commerce found "Common GLP-1 peptide: not detected." Verify it yourself with key VKVA7G3FNMP6.
• What was in the vial: Janoshik customer care told us the only substance their lab identified was mannitol (email excerpt and WhatsApp screenshot above).
• Their claims: the Yiwu Ranbu Global Sources page says its products are made with "strict quality control" and are "safe and effective" (screenshot above).
• Their response: in the WhatsApp screenshots, Irene Yang offered no refund and no replacement for the product that failed, only extra boxes with each new order placed.

That is why we say: do not buy from Yiwu Ranbu E-commerce Co., Ltd or Irene Yang. If they have independent test results that contradict ours, we will publish them.

Part 2: How to test for faketides (fake retatrutide) before you trust a vial

"Faketides" are vials sold as a peptide that contain little or none of it. The Janoshik result above is a real example. Here are the simple checks, in the order we wish we had followed them. All of this is for laboratory research use only. Nothing here is dosing or human-use advice.

1. Start small, pay traceably, and test before you scale

Start with the smallest order you can. Use payment methods with a paper trail where you can. Test what arrives (steps 2 and 3) and wait for the results before placing a bigger order or reselling anything. Do not accept an offer of extra boxes with new orders as a substitute for a verified result.

2. At-home Biuret check: is there a peptide at all?

A Biuret reagent is a cheap lab chemical that turns violet when peptide bonds are present and stays blue when they are not. It is a good first filter for an empty or filler-only vial.

This is the test we wish we had run first. Our Biuret kit cost about $16 and is enough to check more than 120 vials at home. A vial with no peptide in it, like the ones we got from Yiwu Ranbu, would have stayed blue. That would have told us right away the product was bad, and saved us the cost of sending it off for a professional lab test. If you buy from a new supplier, run this on every vial first, and save the lab test for vials that pass.

1. Dissolve the vial contents in a small amount of bacteriostatic water, using the same small volume each time.
2. Mix equal parts of the solution and the Biuret reagent in a clear container.
3. Look at the color. Violet means peptide bonds are present. Blue means none were detected.
4. Run two controls side by side: a blank (water plus reagent, should stay blue) and a known peptide or protein (should turn violet). If the controls fail, the test is not valid.

Limits: Biuret only shows that a peptide is present. It cannot tell you which peptide it is, how pure it is, or how many milligrams are in the vial. A violet result does not prove a vial is retatrutide. A blue result is a strong sign nothing peptide-like is there. Safety: Biuret reagent contains copper sulfate and a strong alkali. Wear gloves and eye protection and follow the reagent's safety data sheet.

3. Send a sample from the vial you actually received to an independent lab

This is the only check that really answers "what is in this vial?" Use a third-party lab that runs HPLC (shows purity and compares against a reference) or LC-MS (confirms identity by molecular mass). Send a vial from your own delivery, not a sample the supplier chose. Our result came from a blind GLP-1 peptide test on a vial from our own stock.

4. Verify the report yourself, and match the batch

A COA (certificate of analysis) is only useful if you can verify it. Look for a unique verification key, then type the lab's own website address yourself. Never trust a PDF the supplier emails you, and never click a "verify" link they send. Then check that the lab name, product, batch code, date and result all match your vial. A COA for a different batch tells you nothing about the vial you hold.

But even a perfect match is not proof. The manufacturer controls the cap color, the labels and the batch codes, so a matching COA only shows that the numbers line up. It does not show that the vial in your hand holds what was tested. Most buyers miss this. Treat a vendor's COA as a good sign at best, and use steps 2 and 3 on your own vials for real proof.

5. Be suspicious of prices far below market

A price far under what established, lab-testing vendors charge needs an explanation. Cheaper is cheaper for a reason. If a supplier cannot show verifiable, batch-matched test results for that price, assume the product is not what the seller says it is.

The moral: cheaper is cheaper for a reason

A low price and a "Verified" badge are not a lab report. The only thing that told us what was in the vial was an independent test. Cheaper is cheaper for a reason. Test before you trust, and avoid vendors who answer a failed test with an offer tied to buying more.

Proof and sources

• Janoshik Analytical test report #250495 (verification key VKVA7G3FNMP6): verify.janoshik.com
• Janoshik customer-care emails, Nov 10-11, 2026 (our question; their reply identifying mannitol)
• Global Sources supplier page for Yiwu Ranbu E-commerce Co., Ltd: ranbu.manufacturer.globalsources.com
• Global Sources inquiry list and chat screenshots (Irene Yang, WhatsApp +852 55098176)
• WhatsApp conversation screenshots with Irene Yang (her responses, including the offer of extra boxes with each new order placed)
• Our Global Sources inquiry to Yiwu Ranbu E-commerce Co.,LTD

Case updates

Further messages from the company, in the order they happened.

For laboratory research use only. Not for human or veterinary use. This post describes our own experience and a third-party lab result for the vial tested; it is not medical advice. Last updated Nov 13, 2026.