Methylene blue

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MedKoo CAT#: 100621

CAS#: 61-73-4

Description: Methylene blue is a synthetic basic dye. Methylene blue stains to negatively charged cell components like nucleic acids; when administered in the lymphatic bed of a tumor during oncologic surgery, methylene blue may stain lymph nodes draining from the tumor, thereby aiding in the visual localization of tumor sentinel lymph nodes. When administered intravenously in low doses, this agent may convert methemoglobin to hemoglobin.

Chemical Structure

Methylene blue
CAS# 61-73-4

Theoretical Analysis

MedKoo Cat#: 100621
Name: Methylene blue
CAS#: 61-73-4
Chemical Formula: C16H18ClN3S
Exact Mass:
Molecular Weight: 319.85222
Elemental Analysis: C, 60.08; H, 5.67; Cl, 11.08; N, 13.14; S, 10.02

Price and Availability

Size Price Availability Quantity
10.0g USD 150.0 2 Weeks
25.0g USD 250.0 2 Weeks
50.0g USD 350.0 2 Weeks
100.0g USD 450.0 2 Weeks
200.0g USD 550.0 2 Weeks
500.0g USD 650.0 2 Weeks
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Synonym: Methylene blue; CI52015.

IUPAC/Chemical Name: 3,7-bis(dimethylamino)phenothiazin-5-ium chloride


InChi Code: InChI=1S/C16H18N3S.ClH/c1-18(2)11-5-7-13-15(9-11)20-16-10-12(19(3)4)6-8-14(16)17-13;/h5-10H,1-4H3;1H/q+1;/p-1

SMILES Code: CN(C1=CC2=[S+]C3=C(C=CC(N(C)C)=C3)N=C2C=C1)C.[Cl-]

Appearance: Solid powder

Purity: >96% (or refer to the Certificate of Analysis)

Shipping Condition: Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition: Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Solubility: Soluble in DMSO, not in water

Shelf Life: >2 years if stored properly

Drug Formulation: This drug may be formulated in DMSO

Stock Solution Storage: 0 - 4 C for short term (days to weeks), or -20 C for long term (months).

HS Tariff Code: 2934.99.9001

Preparing Stock Solutions

The following data is based on the product molecular weight 319.85222 Batch specific molecular weights may vary from batch to batch due to the degree of hydration, which will affect the solvent volumes required to prepare stock solutions.

Recalculate based on batch purity %
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: Frasson M, Faus C, Garcia-Granero A, Puga R, Flor-Lorente B, Cervantes A, Navarro S, Garcia-Granero E. Pathological evaluation of mesocolic resection quality and ex vivo methylene blue injection: what is the impact on lymph node harvest after colon resection for cancer? Dis Colon Rectum. 2012 Feb;55(2):197-204. PubMed PMID: 22228164.

2: Märkl B, Moldovan AI, Jähnig H, Cacchi C, Spatz H, Anthuber M, Oruzio DV, Kretsinger H, Arnholdt HM. Combination of ex vivo sentinel lymph node mapping and methylene blue-assisted lymph node dissection in gastric cancer: a prospective and randomized study. Ann Surg Oncol. 2011 Jul;18(7):1860-8. Epub 2011 Apr 19. PubMed PMID: 21503792.

3: Ceranic MS, Kecmanovic DM, Pavlov MJ, Nale DP, Micev MT, Kovacevic PA, Stamenkovic AB. Validation and feasibility of ex vivo sentinel lymph node "mapping" by methylene blue in colorectal cancer. Hepatogastroenterology. 2010 Sep-Oct;57(102-103):1113-8. PubMed PMID: 21410041.

4: Törnroos A, Shabo I, Druvefors B, Arbman G, Olsson H. Postoperative intra-arterial methylene blue injection of colorectal cancer specimens increases the number of lymph nodes recovered. Histopathology. 2011 Feb;58(3):408-13. doi: 10.1111/j.1365-2559.2011.03755.x. Epub 2011 Feb 16. PubMed PMID: 21323959.

5: Pruthi S, Haakenson C, Brost BC, Bryant K, Reid JM, Singh R, Netzel B, Boughey JC, Degnim AC. Pharmacokinetics of methylene blue dye for lymphatic mapping in breast cancer-implications for use in pregnancy. Am J Surg. 2011 Jan;201(1):70-5. PubMed PMID: 21167367.

6: Xiang J, Xia X, Jiang Y, Leung AW, Wang X, Xu J, Wang P, Yu H, Bai D, Xu C. Apoptosis of ovarian cancer cells induced by methylene blue-mediated sonodynamic action. Ultrasonics. 2011 Apr;51(3):390-5. Epub 2010 Nov 27. PubMed PMID: 21147492.

7: He J, Li S, Shao W, Wang D, Chen M, Yin W, Wang W, Gu Y, Zhong B. Activated carbon nanoparticles or methylene blue as tracer during video-assisted thoracic surgery for lung cancer can help pathologist find the detected lymph nodes. J Surg Oncol. 2010 Nov 1;102(6):676-82. PubMed PMID: 20721962.

8: Jangjoo A, Forghani MN, Mehrabibahar M, Sadeghi R. Anaphylaxis reaction of a breast cancer patient to methylene blue during breast surgery with sentinel node mapping. Acta Oncol. 2010 Aug;49(6):877-8. PubMed PMID: 20429734.

9: Mathelin C, Croce S, Brasse D, Gairard B, Gharbi M, Andriamisandratsoa N, Bekaert V, Francis Z, Guyonnet JL, Huss D, Salvador S, Schaeffer R, Grucker D, Marin C, Bellocq JP. Methylene blue dye, an accurate dye for sentinel lymph node identification in early breast cancer. Anticancer Res. 2009 Oct;29(10):4119-25. PubMed PMID: 19846959.

10: Kerwel TG, Spatz J, Anthuber M, Wünsch K, Arnholdt H, Märkl B. Injecting methylene blue into the inferior mesenteric artery assures an adequate lymph node harvest and eliminates pathologist variability in nodal staging for rectal cancer. Dis Colon Rectum. 2009 May;52(5):935-41. PubMed PMID: 19502859.

Additional Information

Methylene blue (CI 52015) is a heterocyclic aromatic chemical compound with the molecular formula C16H18N3SCl. It has many uses in a range of different fields, such as biology and chemistry. At room temperature it appears as a solid, odorless, dark green powder, that yields a blue solution when dissolved in water. The hydrated form has 3 molecules of water per molecule of methylene blue.  Methylene blue should not be confused with methyl blue, another histology stain, new methylene blue, nor with the methyl violets often used as pH indicators. The International Nonproprietary Name (INN) of methylene blue is methylthioninium chloride.