Frequently asked questions

Research use only (RUO) is a regulatory classification, not a marketing qualifier. It states that a material has been produced and released for laboratory investigation — in vitro work, analytical method development, reference standards, and preclinical study — and has not been manufactured, tested, or authorised for administration to humans or animals. RUO material is not a drug, food, or dietary supplement, and it is not intended for diagnostic or therapeutic use.

Practically, the classification governs three things. First, the quality system behind the vial is designed around analytical identity and purity — see our verification process — rather than pharmaceutical release criteria such as sterility assurance for injectables. Second, the documentation set is analytical: a batch-linked certificate of analysis, method statements, and handling guidance, not prescribing information. Third, responsibility for how the material is used sits entirely with the receiving laboratory, which must hold its own approvals, containment, and disposal procedures. A supplier that labels material RUO and then describes human outcomes is contradicting its own classification.

No. The peptides catalogued on this reference are not approved drugs. They have not been reviewed or authorised by the FDA or by any comparable regulatory authority for human or veterinary use, and nothing stated on this site has been evaluated by a regulator. A small number of peptide sequences exist in approved pharmaceutical products manufactured under entirely separate quality systems; that fact says nothing about research-grade material, which is produced to analytical rather than pharmaceutical release standards and is not interchangeable with an approved product.

Approval status also should not be confused with literature availability. A compound can appear in dozens of PubMed-indexed studies and still have no approved indication anywhere, because publication reflects investigation rather than authorisation. Our reference records separate those two things deliberately: specifications describe what the material is, and the research section describes what has been published about it, without implying regulatory standing. If a supplier presents peptides as approved, cleared, or pharmaceutical-grade without naming the authority and the specific authorisation, treat the claim as unsupported.

They occupy different regulatory categories, different supply chains, and different documentation regimes. A dietary supplement is a consumer product intended for ingestion, sold under food-law frameworks, with labelling requirements built around serving information and ingredient disclosure. A research compound is a laboratory material released against an analytical specification — identity, purity by a stated chromatographic method, water content, residual solvents, endotoxin and elemental impurities where applicable — and is not intended for consumption by anyone.

The practical differences follow from that. A supplement label tells a consumer what to do with the product; a research certificate of analysis tells a laboratory what the material is. Supplement batches are rarely accompanied by lot-linked chromatograms; research batches should be. Supplements are formulated for shelf stability at room temperature; lyophilized research peptides are held desiccated and frozen. Any supplier that blurs the two — supplement-style presentation over research material, or research language attached to a consumer product — is signalling that its category boundaries, and probably its documentation, are unreliable.

Research materials are supplied to qualified laboratories, institutions, and research professionals who are able to receive, store, handle, and dispose of them under their own documented procedures. In practice that means an organisation or individual with a controlled storage environment, a means of recording material receipt against batch identifiers, competence in handling lyophilized solids and solvents, and awareness of the local, state, and federal rules that apply to the acquisition and disposal of research chemicals in their jurisdiction.

Qualification is not a certificate we issue. It is a self-assessment the purchaser makes and remains accountable for, and it is one of the reasons every page of this reference carries the research-use statement rather than burying it. Institutional buyers typically satisfy this through existing procurement and safety review; independent researchers satisfy it by holding equivalent controls, as described in our sourcing standards. If a prospective purchaser cannot describe where the material will be stored, how it will be logged against its batch record, and how unused material will be disposed of, the purchase is premature regardless of who is selling.

A certificate of analysis (COA) is the analytical record for one specific batch. It identifies the material, names the batch, states the date of analysis, lists each test performed with its method and specification, and reports the measured result against that specification. A useful COA is therefore a table of measurements, not a statement of quality — the structure is described in our documentation overview.

What a COA does not tell you is equally important. It describes the material at the moment of testing, so it says nothing about degradation accumulated afterwards in a warm warehouse or a long transit. It reports only the tests listed — a certificate with no endotoxin line has not demonstrated a low endotoxin load, it has simply not looked. It cannot confirm that the vial in your hand came from the batch named, unless the vial carries a matching identifier. And it says nothing about the synthesis route, the manufacturing site, or whether the same specification will be met by the next lot. Read it as evidence of one batch, at one time.

Start with the link between paper and vial. The batch or lot identifier on the certificate must match the identifier printed on the vial label; if the vial carries no identifier, the certificate cannot be attached to it and verification stops there. Next, check that the document names the testing laboratory — letterhead, laboratory identifier, analyst or operator reference, and where applicable an accreditation mark — and that it carries a date of analysis rather than only a print date.

Then check the content. Each result should be paired with a method and a specification, and purity results should be supported by a chromatogram available on request. Compare certificates across two or more batches: results identical to the decimal place across lots indicate a template rather than measurements. Finally, verify externally where possible. An accredited laboratory will confirm whether it issued a report under a given reference. A supplier that cannot produce a batch-specific certificate before you order, or a historical one afterwards, is not operating a retention system — see sourcing standards for the full checklist.

Reversed-phase high-performance liquid chromatography separates the components of a sample by their affinity for a hydrophobic stationary phase, typically a C18 column, as a solvent gradient carries them through. A detector — usually UV absorbance at 214 nm, where the peptide bond absorbs — records each component as it elutes. Purity is reported as the area of the main peak as a percentage of total integrated peak area.

That definition carries two limits worth stating plainly. First, the figure is relative to what the detector sees: species that do not absorb at the chosen wavelength, or that never elute under the chosen gradient, are invisible to the measurement. Counterion content and residual water are not captured by peak area at all, which is why they are specified separately. Second, purity is method-dependent, so a percentage without a stated column, gradient, and wavelength cannot be compared between suppliers. Our release specification and the detail of each gate are set out on the testing page.

Mass spectrometry answers a question chromatography cannot: whether the material is the intended molecule. The sample is ionised — electrospray ionisation is standard for peptides — and the instrument measures mass-to-charge ratios of the resulting ions. Deconvoluting the observed charge series gives an experimental monoisotopic or average mass, which is compared against the mass calculated from the declared sequence and molecular formula. Agreement within a narrow tolerance is identity confirmation; a deviation indicates a different molecule, a modification, or an incomplete sequence.

The technique is also diagnostic about failure. A mass shifted by the residue mass of a single amino acid points to a deletion sequence from synthesis. A shift of plus sixteen suggests oxidation; plus one, deamidation. Because these species can co-elute with the main peak under some gradients, mass data and chromatographic data are read together rather than in isolation. Each reference record — for example BPC-157 or GHK-Cu — lists the declared molecular formula and molar mass used for that comparison, or states that the specification is pending.

Both measure contamination that identity and purity testing will not reveal. Endotoxins are lipopolysaccharide fragments of Gram-negative bacterial cell walls. They are heat-stable, survive processes that kill the organism itself, and are biologically active at very low concentrations, which makes them a significant confounder in cell culture and preclinical work: an experimental effect can originate in the contaminant rather than the compound. Screening is typically performed by a Limulus amoebocyte lysate method and reported in endotoxin units per milligram.

Elemental impurities arise from catalysts, reagents, glassware, and process equipment rather than from the sequence. They are quantified by ICP-MS against the limits set out in ICH Q3D, with particular attention to the class 1 elements. Neither contaminant appears as a peak in an HPLC purity figure, and neither is detectable by inspection of a white lyophilized powder. A certificate that omits both lines has not demonstrated their absence. The thresholds applied at release are published on the testing page.

A failure is a measured value outside a pre-stated specification, not a subjective judgement made after the fact. On the chromatographic gate, it looks like a main-peak area below the release threshold, or a single unidentified impurity above its individual limit even when total purity passes. On the identity gate, it is an observed mass outside the permitted deviation from the calculated mass, or a charge envelope that deconvolutes to a species the sequence does not predict.

On the contamination gates, it is an endotoxin value above the stated units per milligram, an elemental impurity above its ICH Q3D limit, or a residual solvent above its ICH Q3C limit. Water content above specification is also a failure, because excess moisture drives hydrolysis during storage regardless of purity at release. Documentation failures count as failures: a batch record that is unsigned, incomplete, or unmatched to a certificate cannot be released, because the material cannot be traced. Failing material is quarantined and not sold; the specific limits appear under what we reject.

Individually each sign has an innocent explanation; in combination they describe a supplier whose documentation cannot be relied upon. Vials arrive without a batch identifier, or with identifiers that appear on no certificate. Certificates name no testing laboratory — no letterhead, no analyst reference, no accreditation mark. Purity is claimed without a method, or the method is named but no chromatogram is available on request. Reported values are identical across multiple lots, which indicates a template rather than measurements. There is no stated retention or re-test policy, so no historical certificate can be produced. Product naming is inconsistent between the listing, the label, and the certificate.

Presentation is a signal too. Consumer-style outcome language, urgency mechanics, or discount pressure attached to laboratory materials indicate a supplier optimising for conversion rather than documentation. So does an inability to answer procedural questions directly: what fraction of batches is externally verified, how long records are retained, and what happens when results disagree. Our full evaluation criteria are set out under sourcing standards.

Third-party results carry more weight, but the useful position is that both are needed. In-house laboratories are usually competent and are the only practical way to test every batch at the point of manufacture; a supplier with no internal analytical capability is testing nothing routinely. The limitation is structural rather than technical: the laboratory releasing a batch sits inside the organisation that profits from its release, and the failure mode is rarely fabrication — it is the gradual relaxation of judgement on marginal results.

Independent verification closes that gap. A credible programme sends a rotating share of batches to an accredited external laboratory with no commercial relationship to the manufacturer, and requires the external result to agree with the internal one before release. Two questions separate a real programme from a decorative one: what proportion of batches is externally verified, and what procedure applies when internal and external results disagree. A supplier operating such a programme answers both immediately. Our own gate structure is documented on the testing page.

Because purity is not a property of a molecule; it is the output of a measurement, and the measurement is defined by its conditions. The same vial can report different percentages under different columns, gradients, run lengths, and detection wavelengths, because each of those choices determines which species are separated from the main peak and which co-elute inside it. A short gradient that fails to resolve a closely related deletion sequence will report a higher number than a longer one that resolves it. Detection at 280 nm rather than 214 nm will under-report species lacking aromatic residues.

So \"99% pure\" with nothing attached is not comparable to any other supplier's figure, is not reproducible, and cannot be checked. "99.1% by RP-HPLC, C18, UV 214 nm, gradient stated, chromatogram available" is a result: another laboratory can repeat it and agree or disagree. Ask for the chromatogram, not the number. If the method is unstated and the trace unavailable, the claim is a marketing statement, and the correct evaluation — set out in our sourcing standards — is to disregard it.

Lyophilized peptides are comparatively stable solids, but they are not inert. Standard laboratory practice is to hold them desiccated, sealed, protected from light, at −20 °C or colder for long-term storage, and to allow sealed vials to equilibrate to room temperature before opening so that atmospheric moisture does not condense onto cold material. Residual moisture, elevated temperature, and light all drive degradation — hydrolysis, oxidation of methionine, cysteine and tryptophan residues, and deamidation of asparagine and glutamine among the common routes.

Sequence matters: some peptides tolerate ambient excursions for days, others degrade measurably. Solutions are far less stable than solids, and repeated freeze–thaw cycling degrades most sequences, which is why aliquoting under a documented procedure is routine. Every reference record carries the storage conditions and stability notes supplied for that material — see tesamorelin for an example — or states that the specification is pending rather than estimating one. Record receipt against the batch identifier so that any later question about material condition has a documented starting point.

Freeze-drying removes the water that makes peptides labile, and the resulting solid tolerates short ambient excursions far better than a solution does. For typical transit durations, a sealed, desiccated vial shipped at ambient temperature arrives within specification, and published stability data for many sequences supports multi-day room-temperature exposure without measurable change.

Cold packs, by contrast, are not a neutral addition. Gel packs warm progressively over a multi-day transit, and the intermediate temperatures they pass through can be worse than steady ambient; condensation forms on cold vials when the package is opened in a warm room, introducing moisture into a material whose specification includes a water-content limit. Dry ice raises its own handling and carrier constraints. The controlled part of the chain is what happens either side of transit: material is held frozen and desiccated in inventory before shipment, and should be returned to −20 °C or colder promptly on receipt. Where a specific material requires temperature-controlled transport, that requirement is stated on its record — see sourcing standards for handling terms.

No. We do not provide human-use reconstitution or dosing guidance, administration instructions, protocols, or recommendations. These materials are supplied for laboratory research use only and are not for human or veterinary consumption.

The boundary is between neutral research arithmetic and instructions for use: thecalculator can convert researcher-entered mass and liquid volume into concentration, draw volume, and U-100 markings, but it does not select a solvent, target amount, route, frequency, or experimental design. Those decisions belong to the qualified laboratory and its approved study procedure.

Published literature may be indexed with route and frequency exactly as authors reported it. None of that makes a study parameter appropriate for a different model, and no calculator output should be read as a recommendation.