Isosulfan Blue
[CAS# 68238-36-8]

Identification

• Classification: Chemical reagent >> Organic reagent >> Amine salt (ammonium salt)
• Name: Isosulfan Blue
• Synonyms: N-[4-[[4-(Diethylamino)phenyl](2,5-disulfophenyl)methylene]-2,5-cyclohexadien-1-ylidene]-N-ethylethanaminium inner salt sodium salt (1:1); Lymphazurin
• Molecular Formula: C₂₇H₃₁N₂NaO₆S₂
• Molecular Weight: 566.66
• CAS Registry Number: 68238-36-8
• EC Number: 814-985-7
• SMILES: CCN(CC)C1=CC=C(C=C1)C(=C2C=CC(=[N+](CC)CC)C=C2)C3=C(C=CC(=C3)S(=O)(=O)[O-])S(=O)(=O)[O-].[Na+]

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H315-H319-H335
• Safety Statements: P261-P264-P264+P265-P271-P280-P302+P352-P304+P340-P305+P351+P338-P319-P321-P332+P317-P337+P317-P362+P364-P403+P233-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Specific target organ toxicity - single exposure	STOT SE	3	H335
Skin irritation	Skin Irrit.	2	H315

Discovery and Applications

Isosulfan Blue is a synthetic dye belonging to the family of sulfonated triphenylmethane dyes. It is commonly used as a diagnostic agent in medical imaging, specifically in the detection of lymphatic drainage. The compound is characterized by its bright blue color, which is a result of its unique chemical structure that contains sulfonate groups attached to a triphenylmethane core. The discovery of Isosulfan Blue dates back to the mid-20th century when researchers were developing contrast agents for use in medical diagnostics. Its application in lymphatic mapping has proven to be a significant advancement in medical diagnostics, particularly in the treatment of cancer.

The synthesis of Isosulfan Blue involves a reaction between a sulfonated phenyl compound and a triphenylmethane derivative, resulting in a dye with multiple sulfonate groups. These sulfonate groups are important because they enhance the solubility of the dye in aqueous solutions, which is crucial for its use in medical applications. The development of this dye was part of a broader effort to create more effective and visible agents for use in the identification of lymph nodes and other tissues during surgery. The introduction of Isosulfan Blue to medical practice was an important step forward in enhancing the precision of lymphatic mapping techniques.

Isosulfan Blue's primary use is in sentinel lymph node mapping, a technique used in cancer surgery, particularly in breast cancer and melanoma. The dye is injected near the tumor site, and it travels through the lymphatic system, staining the sentinel lymph nodes. Surgeons can then identify these nodes, which are the first to receive drainage from the tumor, and determine if cancer cells have spread to them. This process allows for a more targeted approach to cancer surgery, potentially reducing the need for extensive lymph node removal and minimizing the risk of complications. The use of Isosulfan Blue has significantly improved the accuracy of sentinel lymph node biopsy, allowing for better staging of cancer and improving patient outcomes.

In addition to its medical applications, Isosulfan Blue is used in a variety of industrial applications, including the dyeing of textiles and the coloring of certain products in the food industry. Its vibrant blue color and water-solubility make it suitable for use in these industries, though its use in consumer products is more limited due to regulatory concerns surrounding certain dyes.

In conclusion, Isosulfan Blue is a versatile chemical with a significant impact in the field of medical diagnostics, particularly in cancer surgery. Its ability to accurately map lymphatic drainage has made it an indispensable tool in the surgical treatment of cancer, contributing to more precise and less invasive procedures. Continued research into its uses and potential improvements in formulation may enhance its application in various medical and industrial fields.

References

2012. What is the accuracy of sentinel lymph node biopsy for gastric cancer? A systematic review. Gastric cancer : official journal of the International Gastric Cancer Association and the Japanese Gastric Cancer Association, 15(1).
DOI: 10.1007/s10120-011-0103-8

2017. Sentinel lymph node mapping in endometrial cancer: comparison of fluorescence dye with traditional radiocolloid and blue. Journal of Cancer Research and Clinical Oncology, 143(10).
DOI: 10.1007/s00432-017-2501-8