Actively helping customers, employees and the global community during the coronavirus SARS-CoV-2 outbreak.  Learn more >>

What are the spectral properties of iFluor dyes?

Posted August 20, 2019


Answer
Table 1. Spectral properties of iFluor® fluorescent labeling dyes.
 
 Dye
Absmax (nm)
Emmax (nm)
 ε 1
 Φ 2
 CF at 260 nm 3
 CF at 280 nm4
344
448
20000
0.95
0.83
0.23
402
425
37000
0.91
0.48
0.77
433
495
40000
0.78
0.68
0.3
451 502
40000
0.82
0.45
0.27
491
516
75000
0.9
0.21
0.11
527
554
80000
0.83
0.25
0.11
543
563
90000
0.68
0.26
0.16
541 557
100000
0.67
0.25
0.15
556 569
100000
0.64
0.23
0.14
 iFluor® 560 559 571
130000
0.57
0.048
0.069
568
587
100000
0.57
0.34
0.15
587 603
180000
0.53
0.05
0.04
609 627
110000
0.85
0.32
0.49
638
652
250000
0.29
0.062
0.044
654 669
250000
0.25
0.03
0.03
660 677
250000
0.26
0.07
0.08
669 682
250000
0.63
0.019
0.024
683 700
220000
0.23
0.097
0.094
690 713
220000
0.23
0.09
0.04
712
736
190000
0.14
0.12
0.07
756 777
275000
0.12
0.044
0.039
786
811
250000
0.13
0.1
0.09
801
820
250000
0.11
0.03
0.08
811 822
250000
0.05
0.09
0.15
820
849
250000
N/D5
0.11
0.16
836
876
200000
0.02
0.2
0.09
852
877
250000
N/D5
0.1
0.14
Note:
  1. Extinction coefficient at their maximum absorption wavelength. The units of extinction coefficient are cm-1M-1.
  2. FQY = fluorescence quantum yield in aqueous buffer (pH 7.2).
  3. CF at 260 nm is the correction factor used for eliminating the dye contribution to the absorbance at 260 nm.
  4. CF at 280 nm is the correction factor used for eliminating the dye contribution to the absorbance at 280 nm (for peptides and protein labeling).
  5. Fluorescence intensity is significantly increased upon coupling to proteins.
Additional resources

iFluor™ Dyes and Kits

Protocol for Labeling IgG with iFluor™ 488 succinimidyl ester