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elisa OD calculation - (May/08/2013 )


I need to measure TNFalpha secretion in the cell supernatent. The final volume is 0.5ml. The OD of the standards is pg/ml so do I need to halve the OD's of the test samples as the final volume is 0.5 ml.



No, absorbance is a function the pathlength of the light though the sample in the well (see Beer-Lambert law - so if you loaded 100 ul into each well for both standards and samples then there isn't a problem, results should be directly convertable.


Thanks a lot.