XFD350 tetrazine

• Ex/Em: 343/441 nm
• Extinction coefficient: 19,000 cm^-1M^-1
• Reactive Group: Tetrazine
• Click Chemistry Conjugation: Provides rapid, copper-free labeling of TCO-modified biomolecules
• Moderate Brightness & pH Stability: Ideal for high-abundance targets and maintains consistent fluorescence across a broad pH range (4–11)
• High Contrast: Minimizes spectral overlap with common fluorophores like fluorescein and XFD488, enhancing multiplexing and signal clarity

XFD350, manufactured by AAT Bioquest, is structurally identical to Alexa Fluor® 350 (ThermoFisher). This blue-fluorescent dye exhibits strong absorption and moderate photostability, with consistent fluorescence across a broad pH range (pH 4-11). XFD350 is effectively excited by the 350 nm line of a UV laser, and its moderate brightness and stability make it particularly advantageous for direct imaging of high-abundance targets in both microscopy and flow cytometry applications.

XFD350 tetrazine is particularly useful for labeling TCO-modified biomolecules under copper-free conditions. It reacts with TCO-functionalized molecules, forming a stable conjugate via a dihydropyrazine moiety. This click reaction is favored over others due to its extremely fast kinetics and higher yields under mild reaction conditions, making it a popular choice for researchers.