Buy B12 (Methylcobalamin) in Canada from Anglo Peptides, a Canadian research-grade supplier of the active coenzyme form of vitamin B12. Every vial is produced in a cGMP-compliant facility, lyophilised for stability, and protected from light, and each order includes a batch-specific certificate of analysis. Orders ship same-day in cold-pack packaging and arrive within 1 to 3 business days across Canada. The summary below reflects established biochemistry and the published research literature and is provided for laboratory research context only.

What Is Methylcobalamin?
Methylcobalamin, also written mecobalamin, is one of the two naturally occurring bioactive coenzyme forms of vitamin B12. It is a cobalt-containing corrinoid: a complex corrin ring system chelating a central cobalt atom, with a methyl group bound directly to the cobalt through an unusual carbon-cobalt bond. It differs from the common supplement form cyanocobalamin, which carries a cyanide group and must be metabolically converted before use, and from hydroxocobalamin, an intermediate form. Methylcobalamin and adenosylcobalamin are the two forms used directly by human enzymes. It carries CAS number 13422-55-4, molecular formula C63H91CoN13O14P and a molecular weight of approximately 1344 g/mol. Unlike most compounds in this catalogue, vitamin B12 is an established essential nutrient, so much of the biochemistry below is settled science rather than preliminary research.
Biochemical Role and Mechanism
Methylcobalamin is the obligatory cofactor for methionine synthase, a cytosolic enzyme in one-carbon metabolism. In its catalytic cycle, methionine synthase transfers the methyl group from methylcobalamin to homocysteine, producing methionine, and the cofactor is then re-methylated by 5-methyltetrahydrofolate, regenerating methylcobalamin.[1][3] This reaction has several downstream consequences. Methionine feeds the production of S-adenosylmethionine, the principal methyl donor for DNA, RNA, protein and lipid methylation. The reaction is also the metabolic junction between B12 and folate, so impaired methionine synthase traps folate and impairs DNA synthesis, which is the basis of the megaloblastic changes seen in B12 deficiency. Methylation-dependent processes are likewise essential to myelin integrity and to normal red-blood-cell formation.
Research and Established Applications
Because B12 is an essential nutrient, much of the following is established science, with the neuropathy work being an area of active research.
Deficiency biology. Vitamin B12 deficiency causes megaloblastic anemia and neurological disease, including subacute combined degeneration of the spinal cord; neurological signs can occur even without anemia.[1]
Peripheral neuropathy research. Methylcobalamin in peripheral neuropathy is an active research area. An open-label trial of ultra-high-dose intravenous methylcobalamin reported it was safe and potentially beneficial in peripheral neuropathy with chronic axonal degeneration,[2] while systematic reviews report modest effects, stronger in combination regimens, and note that trial quality is limited.
Research framing. The material supplied here is for laboratory research use only and is not a dietary supplement or medicine.
Stability, Solubility and Handling
The most important handling point for methylcobalamin is light sensitivity. All cobalamins are photolabile, and the active forms, including methylcobalamin, are especially sensitive, degrading to hydroxocobalamin within seconds under UV exposure and breaking down under ordinary fluorescent light.[4] Protect the compound from light at every stage, using amber or foil-wrapped vials and minimal ambient light. It is supplied as a lyophilised powder, reconstituted with sterile or bacteriostatic water for research; aqueous solutions are particularly prone to photolysis, so prepare fresh, keep solutions cold and dark, and use promptly. Store the lyophilised powder cold and dark, with long-term storage frozen. These notes apply to in-vitro and animal research only.
Product Specifications
- Compound: Methylcobalamin (active coenzyme vitamin B12)
- Class: Cobalt-containing corrinoid
- CAS: 13422-55-4
- Molecular formula: C63H91CoN13O14P
- Molecular weight: ~1344 g/mol
- Size: 1 mg per vial
- Form: Lyophilised powder (light-protected)
- Testing: Independent third-party analysis
- Documentation: Batch-specific certificate of analysis
- Origin: Made in Canada
Quality, Testing and Canadian Sourcing
Every batch of Anglo Peptides B12 ships with a lot-specific certificate of analysis. Producing and finishing vials in Canada lets us verify content, protect the light-sensitive material properly, and ship quickly without customs delays. Read more on our Canadian sourcing page. B12 is frequently kept on hand alongside reconstitution supplies and other research compounds in our catalogue.
Methylcobalamin Versus Other B12 Forms
Vitamin B12 exists in several forms that are not interchangeable at the biochemical level, and the distinction matters for any study. Cyanocobalamin is the synthetic, highly stable form used in most inexpensive supplements; it carries a cyanide ligand and is not directly active, requiring metabolic conversion before use. Hydroxocobalamin is an intermediate form and the most photostable of the group. Methylcobalamin and adenosylcobalamin are the two coenzyme forms used directly by human enzymes, methylcobalamin by cytosolic methionine synthase and adenosylcobalamin by mitochondrial methylmalonyl-CoA mutase. Supplying the methyl form therefore provides a coenzyme that does not depend on the conversion steps required by cyanocobalamin, which is the main reason it is selected in research contexts focused on methylation and one-carbon metabolism. The trade-off is stability: the active forms are markedly more light-sensitive, which shapes how the material must be handled.
Considerations for Research Use
Unlike most compounds in this catalogue, vitamin B12 is an established essential nutrient, so the underlying biochemistry is settled rather than preliminary; the research framing applies to how the material is supplied and to specific investigational questions such as high-dose methylcobalamin in neuropathy. The dominant practical consideration is photostability: experiments should control for light exposure, prepare solutions fresh, and document handling, because uncontrolled degradation to hydroxocobalamin will confound any measurement that depends on the methyl form specifically. Verification of identity and purity for each lot remains important, and the certificate of analysis is the reference for the material received. The compound is supplied for laboratory research use only and is not a dietary supplement or medicine.
Reconstitution, Storage and Handling in Detail
Light protection is the defining handling requirement for methylcobalamin. Because the active cobalamins are photolabile, the powder and any solution should be kept in amber or foil-wrapped vials and handled under reduced lighting. For laboratory use, bring the lyophilised powder to room temperature before opening to avoid condensation, then reconstitute with sterile or bacteriostatic water added slowly down the vial wall and swirled gently. Aqueous solutions degrade fastest, so prepare them fresh, keep them cold and dark, and use them promptly rather than storing for extended periods. The lyophilised powder is more stable than solution and is best stored frozen, sealed, desiccated and protected from light for long-term holding, with aliquoting used to avoid repeated freeze-thaw cycles. These are general research-handling conventions consistent with the known photodegradation behaviour of cobalamins; the lot-specific certificate of analysis and its storage guidance should always take precedence.
Frequently Asked Questions
What is methylcobalamin?
How is methylcobalamin different from cyanocobalamin?
Why does B12 need to be protected from light?
Is this B12 a supplement?
Which B12 form is methylcobalamin?
Why must methylcobalamin be protected from light?
Is the underlying B12 science established or preliminary?
How should reconstituted B12 be stored?
What is the role of methionine synthase?
References
- Froese DS, Fowler B, Baumgartner MR. Vitamin B12, folate, and the methionine remethylation cycle – biochemistry, pathways, and regulation. J Inherit Metab Dis. 2019;42(4):673-685. PubMed
- Shibuya K, Misawa S, Nasu S, et al. Safety and Efficacy of Intravenous Ultra-high Dose Methylcobalamin Treatment for Peripheral Neuropathy: A Phase I/II Open Label Clinical Trial. Intern Med. 2014;53(17):1951-1957. PubMed
- Structure of full-length cobalamin-dependent methionine synthase and cofactor loading captured in crystallo. Nat Commun. 2023;14:6391. DOI
- Photodegradation of cobalamins and the relative stability of the cobalamin forms. (Photostability of vitamin B12 derivatives.) 2013. PubMed
Research use only. B12 (methylcobalamin) supplied by Anglo Peptides is intended exclusively for licensed laboratory and academic research. It is not a drug, dietary supplement, or medical product, and is not for human consumption, diagnosis, or treatment.
Researchers who buy B12 Methylcobalamin from Anglo Peptides receive a vial verified to ≥99% purity, batch-tested by Janoshik Labs, and shipped from within Canada. Choose the 1mg size above.






Carlos M. –
Convenient to grab B12 from the same place I order my peptides. Anglo\’s is good quality, clean powder, shipped fast. Will keep including this in future orders.
Rachel T. –
Nice to be able to grab B12 from the same place I order my peptides. Arrived two days after ordering, dissolved cleanly. Fair price and will keep adding this to my orders.
Miles A. –
Anglo Peptides B12 Methylcobalamin is excellent quality. Great to bundle with my peptide orders to hit the free Xpresspost threshold. Arrives properly sealed every time.
Stella K. –
Convenient to order from the same Canadian source as my peptides. Well documented and properly packaged. Fast same-day shipping. Exactly what it needs to be.