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How do I calculate the enery absorved by cells form a UV light - (Jan/14/2014 )

Hey all :)


I am doing some rough experiments irradiating cells with a UV lamp.

I know this is not exactçy the most scientific way to do it, but please bear with me.


How do I calculate the energy (Joules) absorbed by cells?


I suppose I can do this calculation as long as I know the type of lamp (UVC light, I know the wave lenght), the distance of the light source to the cells and the time period the lamp remains on.


Thanks in advance for any help guys.





Not sure if I'm completely wrong but IMO you have to measure the light "amount" which arrives on the cells, there are sensors which e.g. measure watts per square meter or micromoles (μmol) per squaremeter (m-2) per second (s-1) (depends on sensor type).

From this you can calculate joules then using some relationships which are here:

The problem might be how to get the absorbance finally which might be different from emitted radition.


hobgoblin is right, you need to know the power output of the bulb.


If you have access to one, a UV crosslinker (e.g. Stratalinker) usually has this information provided and can time for exact amounts of exposure.


If you need absorbed energy you need to account for the reflected/passed through radiation.