What is Methylene Blue (Methylthioninium Chloride)?
Methylene blue (MB) is a phenothiazine dye with diverse pharmacological mechanisms depending on concentration. At low concentrations (<1 µM): acts as alternative mitochondrial electron carrier — accepts electrons from NADH at complex I and donates to cytochrome c at complex IV, bypassing dysfunctional electron transport chain components and restoring ATP production. At higher concentrations: inhibits guanylyl cyclase (reducing cGMP, causing vasoconstriction), inhibits MAO-A, and acts as redox cycler. FDA-approved (Provayblue) for methemoglobinaemia treatment. Research interest spans mitochondrial dysfunction, neurodegeneration, and nootropic applications.
Mitochondrial electron carrier / redox cycler / MAO inhibitor
Molecular Formula
C₁₆H₁₈ClN₃S
Molecular Weight
319.85 Da
CAS Number
61-73-4
Half-Life
~5.25 hours
Research Applications
Mitochondrial Function / Neuroprotection
Low-dose MB as alternative electron carrier bypasses complex I/III dysfunction in Alzheimer’s, Parkinson’s, and ischaemia models. Increases ATP production, reduces ROS, and protects neurons from excitotoxic death. Preclinical: improved mitochondrial respiration, reduced amyloid-β toxicity.
Tau Pathology Research
MB and its reduced form LMTM (leuco-methylthioninium) investigated as tau aggregation inhibitors in Alzheimer’s models. Clinical trials (TauRx): mixed results but established tau-targeting research platform.
Memory / Cognitive Enhancement Research
Rodent studies: MB improves memory consolidation in fear conditioning and spatial navigation tasks. Mechanism: mitochondrial enhancement in high-metabolic-demand hippocampal neurons. Used as nootropic compound in cognitive function research.
Methemoglobinaemia / Redox Research
MB reduces methaemoglobin (Fe³⁺ haemoglobin) back to functional haemoglobin (Fe²⁺) via NADPH-dependent reduction — FDA-approved mechanism. Reference compound for methaemoglobin reduction studies and haemoglobin redox chemistry.
Key Research Data
Study
Key Findings
Wen et al. 2011 Neuropsychopharmacol
Low-dose MB: memory enhancement in rodents via mitochondrial mechanisms, inverted U-dose-response
Rodriguez et al. 2016 JAMA (TauRx)
LMTM in mild-moderate AD: no benefit in add-on therapy; monotherapy signal — tau research implications
Clifton et al. 2017 Cochrane
Methylene blue in acquired methaemoglobinaemia: effective, fast reversal, standard of care data
Specifications
Format
Oral tablet — 10mg per tablet
Purity
≥99% HPLC
Identity
MS confirmed
Storage
Room temperature, protect from light — photosensitive compound
Colour
Intensely blue — turns urine/stool blue at research doses
FAQ
What is Methylene Blue (Methylthioninium Chloride)?
Methylene Blue (Methylthioninium Chloride) is a Mitochondrial electron carrier / redox cycler / MAO inhibitor. Methylene blue (MB) is a phenothiazine dye with diverse pharmacological mechanisms depending on concentration. At low concentrations (<1 µM): acts as alternative mitochondrial electron carrier — accepts electrons from NADH at complex I and donates to cytochrom...
What research applications does Methylene Blue support?
Low-dose MB as alternative electron carrier bypasses complex I/III dysfunction in Alzheimer’s, Parkinson’s, and ischaemia models. Increases ATP production, reduces ROS, and protects neurons from excitotoxic death. Preclinical: improved mitochondrial respiration, reduced amyloid-β…
How does Methylene Blue compare to similar compounds?
MB and its reduced form LMTM (leuco-methylthioninium) investigated as tau aggregation inhibitors in Alzheimer’s models. Clinical trials (TauRx): mixed results but established tau-targeting research platform….
Does QSC ship Methylene Blue to the USA?
Yes. QSC ships domestically across the USA and to EU, UK, Canada, and Australia. Every batch carries a Janoshik third-party COA confirming ≥99% HPLC purity and MS identity.
