Is Alexa Fluor 700 bright?

Alexa Fluor 700 Brightness and Characteristics

Alexa Fluor 700 is a fluorescent dye used extensively in the field of biochemistry and cell biology for imaging and flow cytometry applications. Its brightness is a crucial factor for its effectiveness in these applications.

Brightness and Efficiency

Alexa Fluor 700 is considered to have moderate brightness when compared to other fluorophores in the Alexa Fluor series. The brightness of a fluorescent dye is determined by two main factors: its extinction coefficient and quantum yield.

• The extinction coefficient measures how efficiently a dye can absorb light at a specific wavelength.
• The quantum yield is a measure of how efficiently the absorbed light is converted into emitted light.

Alexa Fluor 700 has a high extinction coefficient, which means it is very good at absorbing light. However, its quantum yield, while respectable, is not the highest among the Alexa Fluor dyes. This combination results in a dye that is bright enough for most applications but may not be the brightest option available.

Applications and Advantages

Despite not being the brightest fluorophore in the series, Alexa Fluor 700 is highly valued for its photostability and water solubility, making it a reliable choice for long-term imaging and complex biological environments. Its near-infrared emission makes it particularly useful in applications where tissue penetration is important, such as in vivo imaging.

In summary, while Alexa Fluor 700 may not be the brightest dye available, its combination of moderate brightness, excellent photostability, and near-infrared emission spectrum make it a versatile and widely used fluorophore in scientific research.