Question 1

What are research peptides and how are they produced?

Accepted Answer

Research peptides are synthetic chains of amino acids produced for use in controlled, in-vitro laboratory settings. They are manufactured using Solid-Phase Peptide Synthesis (SPPS), a process in which amino acids are added one at a time to a resin-anchored growing chain under controlled chemical conditions. The completed chain is cleaved from the resin, purified by HPLC to remove synthesis by-products, and lyophilized into a stable dry powder. All compounds we supply are SPPS-synthesized, independently HPLC-verified, and dispatched with a batch-specific Certificate of Analysis.

Question 2

Do your peptides contain mannitol or bulking agents?

Accepted Answer

No. Our vials contain pure lyophilized peptide only. No mannitol, excipients, or bulking agents are added. Some suppliers incorporate mannitol to improve the visual appearance of the lyophilized cake, which effectively dilutes the stated quantity and introduces variables into research protocols. What is stated on our vial labels is the actual verified peptide content.

Question 3

Why does my vial look almost empty or have very little powder?

Accepted Answer

Lyophilized peptides are extremely low-density powders. A 5 mg quantity may be barely visible as a thin film or fine residue at the bottom of the vial. This is normal and does not indicate an underfill. The quantity printed on the vial label reflects the actual peptide content verified by gravimetric analysis during quality control, cross-referenced against the batch COA.

Question 4

Do you supply blended peptides?

Accepted Answer

No. We supply single-compound peptides only. Blended or pre-mixed formulations cannot be independently verified for the gravimetric accuracy of each individual component, making reliable quality assurance impossible. Every product in our catalogue is a single compound with its own batch-specific COA.

Question 5

What vial sizes are available?

Accepted Answer

Available sizes vary by compound. Most peptides are offered in 2 mg, 5 mg, and 10 mg options. Select compounds are available in larger formats for institutional procurement. Each product page lists all available sizes with corresponding pricing.

Question 6

What is the shelf life of lyophilized peptides?

Accepted Answer

When stored correctly, lyophilized peptides are stable for 24 months or longer from the date of manufacture. The expiry date is printed on every vial label alongside the batch number. Once reconstituted with bacteriostatic water, the resulting solution should be used within 28 days when refrigerated at 2 to 8 degrees Celsius.

Question 7

How should lyophilized peptides be stored before reconstitution?

Accepted Answer

Store in a cool, dry location away from direct light and moisture. Refrigeration at 2 to 8 degrees Celsius is adequate for most compounds. Peptides with disulfide bonds, complex sequences, or extended storage periods benefit from freezer storage at -20 degrees Celsius. Keep vials sealed until use and avoid repeated thermal cycling.

Question 8

Do you stock bacteriostatic water?

Accepted Answer

Yes. Pharmaceutical-grade bacteriostatic water (0.9% benzyl alcohol) is available to add to your order from the product page. It is shipped with cold-chain packaging as standard. Bacteriostatic water allows reconstituted peptide solutions to remain stable for up to 28 days when refrigerated.

Question 9

What if my reconstituted peptide solution is cloudy?

Accepted Answer

Most peptides dissolve fully in bacteriostatic water. If cloudiness persists after gentle swirling, allow the vial to sit refrigerated for 15 to 30 minutes and try again. Peptides with high hydrophobic content may require initial dissolution in a small volume of 0.1% acetic acid before dilution with BAC water. Do not heat in a microwave or shake vigorously. Contact us if the issue persists.

Question 10

Are research peptides legal to purchase in the United States?

Accepted Answer

Research peptides are not controlled substances under the Controlled Substances Act (CSA) and are legal to purchase in the United States for in-vitro laboratory research purposes. They are not approved drugs and are not licensed for human or veterinary use by the FDA. Purchasers are responsible for ensuring their use complies with all applicable federal, state, and local regulations. Purchasing for any purpose other than in-vitro research is not permitted.

Question 11

Do you accept custom peptide synthesis requests?

Accepted Answer

We do not offer custom synthesis as a standard service. Our catalogue covers the most widely studied peptide compounds. If you require a compound not currently listed, contact us and we can advise on availability and lead times.

Question 12

Is there a minimum order value?

Accepted Answer

No minimum order value applies. You can purchase a single vial.

Question 13

Can you provide reconstitution guidance?

Accepted Answer

General reconstitution guidance is available via our peptide calculator and on this FAQ page. We are not able to provide dosing protocols, research methodologies, or advice on compound selection for specific experimental applications. All compounds are sold exclusively for in-vitro laboratory use.

Question 14

Do you offer volume discounts?

Accepted Answer

Volume discounts apply automatically at checkout when purchasing 3 or 6 vials of the same compound. Institutional and wholesale pricing is available on request for verified research organizations.

Question 15

Do you provide a Certificate of Analysis with every order?

Accepted Answer

Yes. Every compound we stock has a batch-specific Certificate of Analysis produced by an independent, accredited third-party laboratory. The COA is linked directly from the product page and includes the compound name, lot number, molecular weight, HPLC purity percentage, and mass spectrometry identity confirmation. COAs are also available on request by contacting us with your order number.

Question 16

Is testing done in-house or by a third party?

Accepted Answer

All HPLC purity analysis and mass spectrometry identity confirmation is performed by an independent, accredited third-party laboratory. We do not publish in-house test results. A supplier who tests their own products has a direct financial interest in the outcome. Removing that conflict is the foundation of our QC process. The name and accreditation details of our testing laboratory are available on request for institutional records.

Question 17

What is the minimum purity standard?

Accepted Answer

We accept batches at a minimum of 98.0% purity by HPLC. Any batch that tests below this threshold is rejected and not dispatched. Most batches test above 99.0%. The exact purity figure for every lot is stated on the batch-specific COA.

Question 18

What are common impurities found in synthesized peptides?

Accepted Answer

The most frequently occurring impurities in SPPS-synthesized peptides are truncated sequences (chains where synthesis terminated early), deletion sequences (chains missing one or more amino acids), and oxidation by-products. HPLC separates these from the target compound and quantifies their relative proportion. MS-UPLC is used alongside HPLC to confirm that the dominant peak matches the correct molecular weight for the stated sequence.

Question 19

What is the difference between purity and peptide content?

Accepted Answer

Purity is the proportion of the target peptide within the sample, expressed as a percentage of the total measurable content by HPLC. Peptide content refers to the absolute mass of peptide in a vial as stated on the label. A vial labeled 5 mg at 99% purity contains approximately 4.95 mg of the target compound and approximately 0.05 mg of quantifiable impurities. We verify both the label quantity gravimetrically and the purity analytically.

Question 20

Do your compounds undergo endotoxin testing?

Accepted Answer

Endotoxin testing is not part of our standard QC process, as compounds are intended for in-vitro use only. If your research application requires endotoxin-tested material, contact us before ordering to discuss whether this can be accommodated.

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