INTRODUCTION

Methylene blue (MB), a basic thiazine dye has been used clinically for about a century to treat numerous ailments. Primarily used in the treatment of methemoglobinemia, as an antidote in cyanide poisoning, as a biological stain, and as an oxidant-reduction indicator.

The intravenous form of MB is approved by the FDA for the treatment of pediatric and adult patients with acquired methemoglobinemia. MB is an investigational drug being developed by the University of Aberdeen and TauRx Therapeutics that has been shown in early clinical trials to be an inhibitor of Tau protein aggregation. The drug is also of potential interest for the treatment of patients with Alzheimer’s disease.

SynonymsMethylthioninium chloride
Basic blue 9 (C.I. 52015)
CAS no.122965-43-9 (hydrate)
7220-79-3 (trihydrate)
61-73-4 (anhydrous)
EINECS no.602-909-3 (hydrate)
615-731-6 (trihydrate)
200-515-2 (anhydrous)
Molecular formulaC16H18N3S.Cl.xH2O
Molecular weight337.90 (hydrate & trihydrate)
319.85 (anhydrous)
Structure

MEDICAL APPLICATIONS

MethemoglobinemiaMB is employed as a medication for the treatment of methemoglobinemia
Combined with lightMB combined with light has been used to treat resistant plaque psoriasis
Urinary tract infectionMB is a component of a urinary analgesic/anti-infective/anti-spasmodic known as “Prosed DS”, a combination of phenyl salicylate, benzoic acid, hyoscyamine sulfate, and methenamine (aka hexamethylenetetramine and not to be confused with ‘methanamine’)
Cyanide poisoningSince its reduction potential is similar to that of oxygen and can be reduced by components of the electron transport chain, large doses of methylene blue are sometimes used as an antidote to potassium cyanide poisoning
Dye or stainMB is used in endoscopic polypectomy as an adjunct to saline or epinephrine and is used for injection into the submucosa around the polyp to be removed
PlaceboMB has been used as a placebo; physicians would tell their patients to expect their urine to change color and view this as a sign that their condition had improved
Ifosfamide toxicityAnother use of methylene blue is to treat Ifosfamide neurotoxicity
ShockIt has also been used in septic shock and anaphylaxis

OTHER APPLICATIONS

Redox indicatorMB is widely used as a redox indicator in analytical chemistry
Peroxide generatorMB is also a photosensitizer used to create singlet oxygen when exposed to both oxygen and light
Biological stainingIn biology MB is used as a dye for number of different staining procedures, such as Wright’s stain and Jenner’s stain. Since it is a temporary staining technique, MB can also be used to examine RNA or DNA under the microscope or in a gel
AquacultureMB is used in aquaculture and by tropical fish hobbyists as a treatment for fungal infections

Modes of action of Methylene Blue in SARS-CoV-2 infection complications (as per the current ongoing studies. Concrete data to be available soon)

It inhibits SARS-CoV-2 spike ACE2 protein – protein interaction
To treat Cytokinin Storm which is one of the major reason for ADRs, Multiorgan Failure & Mortality
It relieves oxidative stress, ROS and free radicals
It increases systemic vascular resistance (SVR) in septic shock
It causes antifibrotic action in lungs

SPECIFICATIONS
MB offered by Exsyn complies USP & EP pharmacopeia. Please ask our sourcing team if you need detailed specifications.

WRITTEN CONFIRMATION (WC)
ExSyn offers MB with WC certification, so it can be sold to the EU as an API for human consumption.

STORAGE
Temporary storage temperature is below 30°C
Long term storage temperature is 5°C ± 3°C

ExSyn offers MB on commercial scale and welcomes enquiries. No matter the quantity you need, our exceptional quality and service will make ExSyn your supplier of choice! If you need any additional information or SDS, please get in touch with us.

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