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dilution factor, ELISA - (May/12/2013 )

I have a problem in calculating a dilution factor for my elisa samples.hope you guys can help me out.
This is what i did

I have two samples(A & with concentration of sample A 2.93ug/ul (39.3ul sampl + 60.1ul diluent ) and sample B 3.48ug/ul (33.5ul sample + 66.5ul diluent), i diluted these two sample to a concentration of 1.17ug/ul to a final volume of 100ul.these samples are done in duplicates

After elisa based on the standard curve(spline curve) i got a concentrations of sample A 0.423ng/ml and 1.285ng/ml, and for sample B 1.14ng/ml and 1.67ng/ml.

Now i want to know what is the concentration of my protein sample before dilution.

Thanks in advance


Divide your starting concentration (for sample A it is 2.93 ug/ul) by your ending concentration (the concentration of sample you loaded onto your ELISA plate, in this case 1.17 ug/ul) and you will get your dilution factor, which is 2.504. Multiply this number by the output from your ELISA (.423 ng/ul x 2.504) and you get your actual concentration ~2.652 ng/ul. Does this make sense? This example used numbers from Sample A only.