Product details
Vitamin B-12 (cobalamin) is a cobalt-containing organometallic vitamin and an essential cofactor for methionine synthase and methylmalonyl-CoA mutase. It exists in four biologically relevant forms distinguished by the ligand at the cobalt centre — cyanocobalamin (-CN, the synthetic / supplemental form), methylcobalamin (-CH₃, the cytoplasmic methyl-donor form), hydroxocobalamin (-OH), and adenosylcobalamin (5'-deoxyadenosyl, the mitochondrial form). The forms are not interchangeable as standards, so the specific form is the central identity question. B-12 is referenced here as a characterized standard, not for any clinical outcome.
Peptuno supplies B-12 as a reference standard in both cyanocobalamin (CAS 68-19-9) and methylcobalamin (CAS 13422-55-4) forms; specify the form at order placement, with hydroxo- and adenosyl- forms available on request. The release packet states the exact form and salt on every lot, with chemical purity by HPLC, mass-spec identity, and water content; all cobalamin forms are photosensitive and oxidation-sensitive, so storage is refrigerated and light-protected. Confirm the form by COA / label before use, since the forms differ in their applications. This is reference-grade research material, distinct from compounding-scale API supply.
Regulatory note: Specify the exact B-12 form (cyano / methyl / hydroxo / adenosyl) at order placement; the forms are not interchangeable across applications. Confirm form and salt by batch COA / label before use. Peptuno supplies B-12 strictly for Research Use Only; buyers are responsible for verifying ingredient eligibility in their destination market.
FAQ
- Which B-12 form should a lab order, cyanocobalamin or methylcobalamin?
- It depends on the reference need. Cyanocobalamin (CAS 68-19-9) is the more shelf-stable form and the common supplemental and injectable reference; it requires intracellular conversion to the active forms. Methylcobalamin (CAS 13422-55-4) is the directly active cytoplasmic methyl-donor form, preferred where the work needs the active species without the conversion step. Hydroxo- and adenosyl- forms are available on request; specify the form at order placement since the forms are not interchangeable as standards.
- Why does B-12 require refrigerated, light-protected storage?
- All four cobalamin forms are photosensitive — light initiates photochemical degradation of the corrin ring — and the cobalt centre is oxidation-sensitive under unprotected conditions. Refrigerated (2–8 °C) storage with light protection (amber or opaque packaging) preserves the lyophilized material over its shelf life; solutions degrade faster and should remain in the original container until use.
- How is the supplied form documented?
- The exact form and salt are stated on every lot COA, alongside chemical purity by HPLC, mass-spec identity, and water content. Because the forms are not interchangeable across applications, a lab should confirm the form on the COA or label before use rather than relying on the catalog name alone.
Certificate of Analysis (COA)
The per-lot COA for this product will appear here.