Frequently Asked Questions

The 2025–2026 period eliminated several long-trusted names: Peptide Sciences, Amino Asylum, Paradigm Peptides, and Science.bio all closed, restructured, or stopped publishing acceptable documentation. The suppliers that cleared our 2026 blinded HPLC evaluation include ROEHN Research (9.6/10 — top-ranked), Ascension Peptides (9.0/10), EZ Peptides (8.4/10), and Limitless Life Nootropics (8.2/10). Full scoring is in our 2026 supplier evaluation.

ROEHN Research is a US-based research peptide supplier that scored 9.6/10 in our 2026 blinded HPLC evaluation — the highest score we recorded and the only supplier where every tested sample met or exceeded its label claim. Our evaluation is independent: no vendor pays for placement, no affiliate relationship influenced the score. ROEHN is our top-ranked affiliate partner because it earned that rank first; we disclose the relationship transparently. It ships cold-chain as a standard (not a paid add-on), publishes a batch-specific COA with an HPLC chromatogram on every order, and works with named third-party labs. See our 2026 full evaluation report for methodology.

Look for three things: a named editor, a disclosed methodology, and affiliate disclosure. Peptide Research Review publishes all three — editor Mootez Chachia, a full methodology page explaining how the 38 blinded HPLC samples were collected and scored, and clear disclosure of the ROEHN affiliate relationship. Sites that omit any of these, or that rank vendors without publishing their testing process, are giving you marketing dressed as editorial.

Four non-negotiables: (1) A batch-specific Certificate of Analysis — tied to your exact lot, not a generic spec sheet reused across every product. (2) HPLC purity at or above 98%, shown with an attached chromatogram. (3) A named third-party lab — Janoshik Analytical, MZ Biolabs, or Colmaric Analyticals are the recognized labs in this space; an unnamed or in-house lab is a red flag. (4) Mass-spec identity confirmation — proof the vial contains what the label claims, not a cheaper substitute. Cold-chain shipping is a fifth requirement for temperature-sensitive compounds (BPC-157, NAD+, GLP-1 peptides).

International vendors introduce two risks domestic ones do not: customs and cold chain. Packages crossing borders can be held, seized (depending on the compound and jurisdiction), or delayed in a warm warehouse for days. Temperature-sensitive peptides degrade in transit under those conditions. If you purchase from an international supplier, confirm cold-chain packaging, realistic transit times, and whether the vendor has experience with your country’s customs procedures. For most US researchers, domestic suppliers with verified cold-chain shipping carry meaningfully lower risk.

Between 2025 and 2026, several long-running peptide vendors went dark or materially changed their documentation practices. Peptide Sciences, Amino Asylum, Paradigm Peptides, and Science.bio are among the names that closed, restructured, or stopped publishing verifiable COAs. The cause in most cases was a combination of regulatory pressure on gray-market research chemical sales and the operating difficulty of maintaining documentation discipline at scale. Our 2026 supplier evaluation covers the current verified vendor list.

A Certificate of Analysis (COA) is a lab-issued document that reports the analytical test results for a specific production batch of a compound. A legitimate COA for a research peptide should include: the compound name and lot number, HPLC purity (expressed as a percentage area with a chromatogram), mass-spectrometry identity confirmation matching the expected molecular weight, the issuing lab’s name and date, and ideally water content (Karl Fischer) and appearance. Without a real COA, you have no independent verification of what is in the vial — you are taking the vendor’s word.

The research community broadly treats 98% as the floor for research-grade peptides. Vendors that report 95–97% are not automatically unreliable, but you should read the chromatogram yourself — some unresolved impurity peaks can hide within that margin. Anything below 95% is genuinely concerning for research use. The HPLC figure should be accompanied by a chromatogram showing the peak area integration, not just a bare number.

Three labs are widely recognized in the research peptide space: Janoshik Analytical, MZ Biolabs, and Colmaric Analyticals. These labs have public track records, their reports circulate in independent community forums, and forged reports from named labs are harder to produce credibly than documents from unnamed sources. An in-house lab or a COA with no lab name listed should be treated as unverified.

Red flags for a fake or recycled COA: (1) The lot number on the COA does not match your order or vial. (2) The test date is missing, very old, or implausible. (3) The lab name is absent or is an entity you cannot verify independently. (4) The chromatogram shows a suspiciously perfect single peak with no baseline noise — real HPLC traces have variation. (5) Every product on the vendor’s site lists the exact same purity (e.g., 99.9%) — statistically improbable across a full catalog. Our methodology page explains how our blinded HPLC process catches these issues.

Blinded HPLC testing means samples are submitted to an independent laboratory under a code, not under the vendor’s name, so the lab has no incentive to pass or fail any particular supplier. Peptide Research Review submitted 38 samples across 8 US suppliers in 2026 using this method. The results — which suppliers’ samples met their label claims and which did not — drive our vendor scores. Unblinded testing, or testing conducted by the vendor itself, is not independent verification. Full methodology is at /methodology.

The site covers the major research peptides: BPC-157, TB-500, Semaglutide, Tirzepatide, Retatrutide, NAD+, CJC-1295/Ipamorelin, Sermorelin, PT-141, Melanotan II, and others. Each compound has a reconstitution calculator at /tools, a COA reading guide at /guides, and where applicable a buying guide at /where-to-buy.

BPC-157 (Body Protection Compound-157) is a 15-amino-acid synthetic peptide fragment studied for tissue-repair research in animal models. It is not an FDA-approved drug and has not completed human clinical trials. Published research has explored its effects in rodent models of tendon, muscle, and gastrointestinal tissue. It is sold for laboratory research use only — not for human consumption or therapeutic application. See our BPC-157 reconstitution calculator and BPC-157 buying guide.

Semaglutide is a GLP-1 receptor agonist that is FDA-approved (as Ozempic/Wegovy) for specific clinical indications. Research-grade Semaglutide is a separate category: it is sold as a lyophilized research compound for laboratory investigation, not as a pharmaceutical product and not for human use. Research suppliers selling Semaglutide for research use operate in a legal gray area — the compound is a known pharmaceutical, but the research-use framing changes how it is regulated at point of sale. See our Semaglutide buying guide for sourcing context.

BPC-157 is a synthetic peptide fragment studied in gastrointestinal and musculoskeletal tissue-repair research. TB-500 is a synthetic fragment of Thymosin Beta-4, studied separately and sometimes alongside BPC-157 in recovery research (the so-called “Wolverine stack” in researcher shorthand). They have different amino-acid sequences, different molecular weights, and distinct published research profiles. They are sometimes co-purchased because the research areas overlap, not because they are interchangeable. See our BPC-157 and TB-500 buying guides for compound-specific sourcing notes.

No. All dosing ranges shown on this site are labeled “published research literature range” and are drawn from peer-reviewed research. They are reference data for researchers reviewing the literature — not personal dosing advice, medical guidance, or a protocol recommendation. All compounds covered here are for laboratory research use only.

The legal status of research peptides in the US is compound-specific and framing-dependent. Most research peptides are sold and purchased legally as “research chemicals for laboratory use only, not for human consumption.” They are not FDA-approved drugs and are not sold through licensed pharmacies. The FDA has issued warning letters to vendors that market research peptides with therapeutic claims. Legality depends on the compound, how the vendor markets it, and how it is used. This is informational content, not legal advice — confirm the regulatory status of any specific compound before purchasing.

The “research use only” (RUO) label is a legal designation indicating the product is sold for in vitro or laboratory research — not for human or animal therapeutic use. Vendors use this framing to operate outside the FDA drug approval framework. The designation is legitimate when compounds are genuinely used in laboratory settings; it does not provide legal cover if a vendor markets the product with therapeutic claims or if a buyer uses it outside a research context.

Yes. The FDA has taken action against peptide vendors for: marketing with therapeutic or human-use claims, selling compounded peptides outside the compounding pharmacy framework, failing to maintain adequate documentation, and making unsubstantiated health claims in marketing. The closures of 2025–2026 (Peptide Sciences, Amino Asylum, Paradigm Peptides, Science.bio) occurred in part because of this enforcement environment. Vendors that maintain strict research-use framing and documentation discipline carry lower regulatory risk than those that market aggressively toward human use.

Peptide Research Review carries a single affiliate relationship: ROEHN Research. ROEHN pays a commission on reader-referred orders (code FREE15). That relationship is disclosed on every page where ROEHN is linked. No other vendor sponsors, pays for, or influences editorial content. The 2026 vendor scores were determined by blinded HPLC testing conducted before any affiliate arrangement was in place. We accept 0 sponsored placements and have no undisclosed commercial relationships. See our methodology and about page.

Reconstitution is the process of dissolving a lyophilized (freeze-dried) peptide in a liquid — typically bacteriostatic water — to produce a solution. Peptides are lyophilized for stability: the freeze-dried form is far more stable for shipping and storage than a liquid solution. Once reconstituted, the window for use shrinks (typically 14–30 days refrigerated, depending on the compound). Our reconstitution calculators help determine the concentration that results from a given vial size and water volume.

Bacteriostatic water (BAC water) is sterile water preserved with 0.9% benzyl alcohol, which inhibits bacterial growth. It is the standard diluent for research peptide reconstitution because it allows a multi-use vial to remain viable for up to 28 days after the first use — plain sterile water does not have this property. BAC water is available without a prescription from pharmacies, medical supply retailers, and some online sources.

Most reconstituted peptides should be refrigerated (2–8°C) immediately after mixing and used within 14–30 days, depending on the compound. NAD+ is the most thermally fragile compound covered here — typically used within 14 days reconstituted. Freeze-thaw cycling degrades peptides; a reconstituted vial should not be repeatedly frozen and thawed. The lyophilized (unreconstituted) compound has a longer shelf life but should also be kept away from heat, light, and humidity. Compound-specific storage notes are on each calculator page.

Each compound at /tools has a dedicated calculator. Enter your vial size (in mg) and the volume of bacteriostatic water you plan to add (in mL). The calculator outputs: the resulting concentration in mcg/mL, how many mcg are in each unit on an insulin syringe, and a concentration table across common water volumes and vial sizes. This is purely arithmetic — it does not recommend a dose or usage amount. That determination belongs to the researcher, based on the published literature.

Vial size affects concentration math and per-dose cost, not inherent quality — assuming both vials come from the same batch with the same COA. A 10 mg vial is the same compound as a 5 mg vial; which to purchase depends on the protocol’s volume requirements. Where vial size does matter is that larger vials from a vendor with poor storage practices represent a larger at-risk investment. Verify COA and cold-chain before ordering in any size.

The quiz at /quiz asks a few questions about your research focus and returns compound-specific starting points — which calculator, buying guide, and article are most relevant. It does not ask for personal health information and does not provide medical advice.