MB™ 543 is a very hydrophilic, water-soluble orange fluorescent dye. Structurally related to Alexa Fluor® 546 dye, MB™ 543 dye contains an additional, negatively charged sulfo group (SO3H) to improve water solubility and minimize self-quenching. Characteristic features of MB™ 543 are strong absorption, high fluorescence quantum yield, high photostability, and pH insensitivity from pH 3 to pH 10. MB™ 543 is a highly suitable dye for single-molecule detection applications and high-resolution microscopy such as PALM, dSTORM, STED etc.
MB™ 543 Alkyne reacts with azides via a copper-catalyzed click reaction (CuAAC) to form a stable triazole linker. A probe for copper-less detection (MB™ 543 DBCO) is also available for application where the presence of copper is not acceptable.