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STAR 440L

STAR 440L (Ex-Max 432 nm/Em-Max 511 nm)

abberior STAR 440L is a long Stokes-shift dye optimized for STED and confocal microscopy in the blue-green spectral range. It shows a Stokes-shift of approx. 80 nm. As all long Stokes-shift dyes, it shows a broad excitation and emission band: It can be excited between 400 - 470 nm and emits between 490 - 550 nm. For STED microscopy, abberior STAR 440L can be most efficiently used with STED laser wavelengths between 590 - 610 nm. It is therefore well suited for 2 color (STED) imaging together with our abberior STAR GREEN or abberior STAR 488. The hydrophilic properties of abberior STAR 440L conjugates preclude unspecific binding of this dye and thus decrease undesired background fluorescence. Our abberior STAR 440L can substitute dyes like ATTO® 425 or BD Horizon® V500. abberior STAR 440SXP has been renamed abberior STAR 440L. The structure of the dye has not changed. Best results are obtained with freshly prepared samples.

Excitation & emission spectra

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Key facts

Excitation maximum
432 nm
Emission maximum
511 nm
Optimal laser line
405
Extinction coefficient
33000

STAR 440L has an excitation maximum at 432 nm and an emission maximum at 511 nm, a Stokes shift of 79 nm. Its extinction coefficient is 33000 M⁻¹cm⁻¹. It is optimally excited by the 405 laser line.

Frequently asked questions

What is STAR 440L?
abberior STAR 440L is a long Stokes-shift dye optimized for STED and confocal microscopy in the blue-green spectral range. It shows a Stokes-shift of approx. 80 nm. As all long Stokes-shift dyes, it shows a broad excitation and emission band: It can be excited between 400 - 470 nm and emits between 490 - 550 nm. For STED microscopy, abberior STAR 440L can be most efficiently used with STED laser wavelengths between 590 - 610 nm. It is therefore well suited for 2 color (STED) imaging together with our abberior STAR GREEN or abberior STAR 488. The hydrophilic properties of abberior STAR 440L conjugates preclude unspecific binding of this dye and thus decrease undesired background fluorescence. Our abberior STAR 440L can substitute dyes like ATTO® 425 or BD Horizon® V500. abberior STAR 440SXP has been renamed abberior STAR 440L. The structure of the dye has not changed. Best results are obtained with freshly prepared samples.
What laser excites STAR 440L?
STAR 440L is optimally excited by the 405 laser line. Its excitation maximum is 432 nm.