The inner filter effect is important in Fluorescence quenching as it can have an effect on your emission intensity during the experiment.  One of the biggest causes of the inner filter effect is the re-absorption of your emitted light by your quencher.  This becomes important because as you carry out a Stern-Volmer analysis the concentration of you quencher increases, and therefore the ability of your quencher to absorb the emitted light will also increase.  

You can correct for the inner filter effect by applying a correction factor:

check out the links below :

One leads you to a paper and the other to a students PhD thesis (which you can download at the bottom of the page) where a correction factor is explained. 

http://pubs.acs.org/doi/abs/10.1021/jp2082853

http://ecommons.usask.ca/handle/10388/ETD-2012-11-765

Thank you dear Adam Langlois 

I was read some more papers related to inner filter effect .

Those papers i found that 

When the inner filter is reason for the quenching its  stern Volmer equation showing that liner curve and static quenching. Is it there any relation .

My question is here  dynamic quenching is possible or not. 

As Adam mentioned, you can correct for the inner filter effect relatively easily.

F-corrected = F-observed*10^((OD-excitation+OD-emission)/2)

If after the correction is applied you have a linear Stern-Volmer plot you than only have one type of quenching. If you still have a curved plot you may have both dynamic and static quenching.

Distinquishing between static and dynamic quenching is slightly more complicated, since the Stern-Volmer plots for each are linear (with both together it becomes hyperbolic). The distinguishing feature is that increased temperature increases the SV plot slope, K, for dynamic quenching (more collisions) and usually decreases slope for static quenching (weaker association).

See the Lakowicz text for more details.

OK... If you are trying to determine if you have static or dynamic quenching (or a mixture of the two) there are a few things that you can do.

1)  It sounds like to are plotting the ratio of the fluorescence intensities as a function of the quencher concentration. 

You could also plot the ratio of the excited state lifetimes as a function of the quencher concentration.  

If you have dynamic quenching (an excited state process) the ratio of the lifetimes will give you the same curve as the ratio of the fluorescence intensities.  

If you have static quenching the lifetime should not change (static quenching is a ground state process).  

therefore if you have static quenching you will see a flat-line at 1 when you plot the ratio of the fluoescence lifetimes as a function of the quencher concentration.  

If you have both static and dynamic quenching the ratio of the fluorescence intensities as a funchtion of quencher concentration should give you a quadratic curve.   

If you do the experiment with the lifetimes you will get a strait line which will correspond to the dynamic component only.

2)  you could also do the experiment by changing the sample temperature.  

if you have dynamic qhenching the slope will increase as you increase the temperature (due to increased difustion rates)

If you have static quenching the slope will decrease (the ground state association is weak and you will break the association bonds by heating leading to less quenching).

As christopher said above:  See Lakowicz (principals of fluorescence spectroscopy) 

There is another way to greatly reducing the influence of inner filter effects:

In most spectrofluorometers, 10 mm cuvettes are used, the excitation beam is centered and detected emission area is also centered. That is, pathlengths of about 5 mm are used. By reducing the used pathlength, you can strongly reduce inner filter. There are two ways for doing this: use a cuvette with smaller x,y size or move the cuvette holder so, that the measured cuvette area is near the corner. Et voilà, small spectral distortion by re-absorption even at high optical densities

HI

What can i use  inner filter equation?

what,s Aexi and Aemi?

Dear all, your discussion is very useful to me. but still I am not cleared. @Adam Langlois mentioned "the inner filter effect is the re-absorption of your emitted light by your quencher"  my doubt is quencher also absorb the fluorescence light, so intensity was decreased in Stern-Volmer and FRET mechanism. What is differences between energy transfer mechanism such as FRET, Stern-Volmer, IFE and what is the role of static/dynamic quenching in above mechanism?

Please answer me, if anything I wrongly understand, Sorry and educate me.

The inner filter effect is the reabsorption of fluorescence light. The most suitable for the initial acquaintance is Parker's book:

C.A. Parker "Photoluminesence of Solutions", 1968.

In this book you will learn what is Stern-Volmer equation and self-quenching of fluorescence. All are different phenomena.

Hi, basically the analyte itself can be a quencher. Am I correct?