Fluorescein is a diagnostic agent which is used to diagnose various vascular disorders, such as retinal disease macular degeneration, diabetic retinopathy, inflammatory intraocular conditions, and intraocular tumours. During open-heart surgery, a diluted form of Fluorescein Sodium is used to localise multiple ventricular septal defects to find out the presence of any defect.
Since it is used in injectable and sterile ophthalmic solutions. It should be used in high purity and meet the purity pharmacopoeia requirements.
Hygroscopicity of Fluorescein Sodium
Fluorescein sodium is highly hygroscopic. It has a strong affinity for water molecules because it immediately binds water molecules during synthesis, purification or handling. The addition of water decreases the potency of fluorescein sodium so it becomes lumpy or terry and changes its colour. It may also expire. It can go out of the specifications as per the Pharmacopeia norms.
All the known processes of synthesizing fluorescein sodium utilize water as a solvent due to which the resulting fluorescein sodium contains a substantial amount of bound water molecules and its removal is very difficult.
A new process for preparing crystalline Fluorescein Sodium
The research and development team of Macsen Labs has invented a novel process of making fluorescein sodium in which the resultant product is almost free of water, is of high purity and has a free-flowing bright orangish colour/ appearance.
Since this process is novel, inventive, advantageous and scalable we have filed a patent for this process. The title for this patent is “Process for the preparation of crystalline fluorescein Sodium from diacetylfluorescein or Fluorescein”.
The team at Macsen Laboratories are highly confident that this patent would be granted by the patent authorities in several countries. Macsen Laboratories has been manufacturing this API for many years, but this gives us an edge over others in the market with more technically competent products.