I have this assay that requires a final volume less than 1 ml which can not be measured by the spectrophotometer so can I use the ELISA reader instead.

PLease reply if you know any info on this issue

How small is the volume?

You can always purchase a micro-cuvette for your spec.

Fisher Scientific carries 10, 30, 40, 100, 300 uL cuvettes

Here is a Link to Fisher's micro-cuvettes


Otherwise, you can always think about using a Nano-Drop Spectrophotometer or Fluorometer. These are cuvette-less specs which measure using only 1 uL of sample.

Check out these discussion on our board about this product -

NanoDrop Spectrophotometry - Scientist Solutions Thread

NanoDrop Meter - Scientist Solutions Thread

As Tony said, your best bet is to get a microcuvette.

However, to answer your question: It may be possible to use a microplate. We have adapted many of our spectrophotometric protocols to microplates to save on reagent and time. Note that in a plate, since you don't have a 1-cm path length, you cannot use extinction coefficients to calculate your concentration.

Thanks for all of ur useful information.

If your volume is more than 400L you may still be able to use a 1mL cuvette. Look to see how high up the cuvette the light beam passes. On our machine it is quite low down so we can use 400L volumes in our 1mL cuvette. Maybe the manufacturers have info on this.