LSM 710 and LSM 780
LEFT TOOL AREA AND HARDWARE CONTROL TOOLS
Systems
Processing Tab
Carl Zeiss
02/2010 M60-1-0025
e
127
5.3.10.2
Ratiometric Dyes
•
Fura-2, Indo-, SNARF, Cameleon, Ratiometric Pericam, Phluorin.
•
Display fluorescence ratio R over time
•
Display fluorescence ratio R corrected for background/autofluorescence over time
•
Calculate absolute ion concentrations (pixel by pixel) via titration calibration (known ion concentrations
applied to the cells – in situ – or in solutions – in vitro or equation calibration where possible [Fura-2,
Indo-, SNARF]
•
Calculation of R eliminates artifacts and uncertainties caused by
−
inhomogeneous dye distribution
−
photobleaching
−
may be applied with moving cells.
Ratiometric Dyes - Online Ratio
(Fig. 135)
R(t1) = F1(t1) / F2(t1), R(t2) = F1(t2) / F2(t2) ...
Ratiometric Dyes - Calibration
(Fig. 136)
•
Subtract background/autofluorescence images from raw images to obtain
R
korr
[=F
1
-F
1Background
)/(F
2
-F
2Background
)]
when calibration reference is not obtained with the experimental sample (in situ).
•
Calculate ratio R.
Fig. 135
Ratiometric Dyes – Online ratio