Resazurin (Na Salt), 5g

A blue fluorogenic dye supplied by STEMCELL Technologies, Resazurin (Sodium Salt) functions as a redox indicator in cell viability and proliferation assays for bacteria, yeast, or mammalian cells. The blue form of the dye is irreversibly reduced by enzymes in viable cells to generate a highly red-fluorescent product, resorufin, which can be detected by flow cytometry, fluorescence microscopy, and high-throughput screening methods. Because the dye is minimally toxic to living cells, it is suitable for use in long-term cell culture. It has also been used to assay L-glutamate and to measure the metabolic activity of mitochondria.

Alternative names listed in the documentation include 7-hydroxy-10-oxidophenoxazin-10-ium-3-one, sodium and Diazoresorcinol, sodium salt. The substance is identified by CAS Number 627-58-13-8, with the molecular formula C₁₂H₆NO₄ · Na and a molecular weight of 251.2 g/mol. It is supplied as a crystalline solid. The resorufin product exhibits an excitation range of 530 - 545 nm and an emission range of 585 - 595 nm, with a stated maximum at ~595 nm. Solubility guidelines indicate ~5 mg/mL in phosphate-buffered saline (pH 7.2) and ~0.5 mg/mL in ethanol, DMSO, or DMF. Recommended storage is at 15 - 25°C, protected from prolonged exposure to light, and the product remains stable until the expiry date (EXP) on the label.

Documented applications include enzyme assays, cytotoxicity, proliferation and viability assays, flow cytometry, fluorescence microscopy, fluorometry, and spectroscopy. The product has been verified for analyzing hematopoietic cells cultured in StemSpan™ SFEM and StemSpan™ SFEM II. According to the safety data sheet, the substance is classified for skin corrosion/irritation (Category 2), serious eye damage/eye irritation (Category 2A), and specific target organ toxicity on single exposure (Category 3), with hazard statements covering skin irritation, serious eye irritation, and respiratory irritation. Recommended personal protective equipment includes safety glasses, compatible chemical-resistant gloves, and a lab coat.