Frequently Asked Questions

Uzorak.com is an independent peptide testing service focused on the EU, accepting samples from worldwide. The laboratory is located in Zagreb, Croatia (EU), the home of BPC-157. Uzorak tests research peptides, proteins and other compounds for purity and mass (amount) by HPLC-UV and for bacterial endotoxin, and offers LC-MS analysis. Every report can be verified online with its sample ID.

Testing is performed at Stamper Lab d.o.o., a company registered in Zagreb, Croatia (EU), MBS 081707380.

Both. Uzorak accepts samples from individuals and researchers, as well as bulk and repeat testing from companies and group tests.

Yes. Uzorak accepts samples from worldwide.

Uzorak does not manufacture, sell or ship peptides. Uzorak only tests samples sent by customers, and reports the result as measured.

Testing is performed by Stamper Lab d.o.o., a company registered in Zagreb, Croatia (EU), MBS 081707380. Every Uzorak report has a unique sample ID and can be checked at uzorak.com/verify, and every Standard mass/purity report comes with the original Agilent instrument data output attached. Uzorak is listed on PeptideCompare.eu, Peptigrity and PeptideBenchmark, and is the partner testing lab for Peptaura (announced 1 Oct 2026).

No. ISO/IEC 17025 accreditation is granted method by method, and every accredited result must be metrologically traceable, so it cannot apply to research-use-only (RUO) compounds. The same goes for GMP and GLP frameworks. Testing is performed in line with such procedures, but the accreditations themselves do not apply to RUO compounds.

Since March 2026, Uzorak has performed close to 2,000 tests on RUO samples.

• First to introduce to RUO compound testing: impurities by HRMS (including untargeted search), MS/MS amino acid sequence verification, and tandem fingerprint comparison.
• Raw data is included with every Standard mass/purity report.
• Standard results take 2–5 working days, often within 48 hours for smaller orders (under 5 samples).
• Standard testing uses non-routine methods: 20+ dedicated methods for better impurity separation.
• Endotoxin testing uses FDA-licensed Charles River Endosafe cartridges.
• Chat support for questions, quotes and orders, during and after testing.

Standard mass/purity testing (HPLC-UV) costs from $200 depending on the peptide, because each peptide needs its own reference standard and method. Examples: BPC-157 $200, TB-500 $200, semaglutide $300, tirzepatide $300, retatrutide $300, GHK-Cu $240. An additional vial of the same peptide is $60. Advanced LC-MS analysis is $1,080. Endotoxin testing is $180 per vial. Bulk and company custom pricing discounts are available. Promotions run often, sometimes up to 35% off.

Standard mass/purity: 2–5 working days after the sample arrives. Advanced LC-MS: 4–8 working days. Urgent processing can be selected at checkout.

Yes. Contact info@uzorak.com, or @uzorak or @lexhr on Telegram.

You can order on the website, by email or by chat on Telegram.

Website:

1. Choose the peptide and the test at uzorak.com.
2. Pay by card, Apple Pay, Google Pay or crypto (USDT/USDC).
3. Post the samples to the lab address shown in your order confirmation.
4. Get your report online, with a verification link.

Email: info@uzorak.com · Telegram: @uzorak

You receive an email confirmation with a sample ID for each vial, shipping instructions (EU, US, UK and worldwide) and other details. Once the samples are tested, you receive the results and verification links by email.

1. Once an order is paid, you receive sample IDs for each vial, plus shipping details and instructions, by email.
2. Label each vial with its sample ID (a label, sticker, marker, tape or any other method).
3. Pack the sealed vial in padding inside a small box or padded envelope.
4. Post it to the lab address in your order confirmation and keep the tracking number.
5. Reply to the confirmation email with the tracking number, so the lab can process it as fast as possible.

One sealed vial per test: one vial for mass/purity, one vial for endotoxin, and so on.

More than 40, including BPC-157, TB-500, semaglutide, tirzepatide, retatrutide, GHK-Cu, ipamorelin, CJC-1295, MOTS-C, NAD+ and others. The full list with prices is on the pricing page. Some peptides might not be listed; contact Uzorak for pricing.

No. Testing uses up the sample, and any remainder is disposed of safely.

Yes. The customer decides whether a report can be shared.

A Uzorak standard test report shows purity (how much of the sample is the target peptide, %), mass (how many mg of peptide are in the vial), and identifies the compound by retention time (RT).

In the peptide community, "mass" means the amount (potency) of peptide in the vial, in mg. Uzorak measures it by HPLC-UV against a reference standard of known concentration. It is not a mass-spectrometry measurement of molecular mass; molecular identity is confirmed in Uzorak’s LC-MS service.

Purity and amount are different measurements. Purity says how clean the peptide is. Mass says how much peptide is in the vial. A vial can be 99% pure but contain 8 mg instead of the 10 mg on the label. That’s why Uzorak reports both.

By reversed-phase HPLC with UV detection at the wavelength set for each compound. Purity is the main peak’s area as a percentage of the total UV signal.

By HPLC-UV: the peak area of the sample is compared with the peak area of a reference standard of the same peptide at a known concentration. The result is reported in mg of peptide per vial.

With the Charles River Endosafe nexgen-PTS. Its FDA-licensed cartridges use the kinetic chromogenic LAL method described in USP <85> and Ph. Eur. 2.6.14. The result is a number in EU per vial, within the range chosen at checkout (1–100, 10–1,000 or 100–10,000 EU/vial). Each endotoxin test needs its own extra vial.

Usually because they tested different vials, batches or dates, or used different methods. A Uzorak report describes the exact vial tested, on the date tested.

No. A Uzorak report covers the specific vial tested. Testing more than one vial from a batch gives a better picture.

Open uzorak.com/verify and enter the sample ID, or use the verification link on the report. If the details don’t match the copy you were given, the copy has been altered.