RNA quantification in microplate reader - (Jul/02/2009 )
I was wondering if its ok to use a microplate to quantify RNA.
i.e. read absorbance in a microplate reader at 260 and 280nm instead of a cuvette
Is this possible? How would I calculate the concentration?
Most microtiter plates are not transparent at 260 nm. You would probably be better off using an RNA binding dye. Read the Molecular Probes (now Invitrogen) site for information about RNA selective dyes. One of the Picogreen series should work.
Absolutely you can measure 260/280 in a microplate. There are several brands of inexpensive UV-transparent microplates available. Greiner even makes a UV plate for DNA RNA and protein measurements that holds as little as 3ul. If you use it with an Omega reader from BMG Labtech, which can collect a full UV/Vis spectrum instantly, it's like have a Nanodrop for 384 samples at once.
Yes you sure can and in fact that is a smarter way to read many samples than to use cuvettes. There are disposable uv plates as well as quartz plates available commertially.
Only thing that has to be taken care is to set the path length corerction as by changing the volume, tht path length wll change in a microplate reader. Most readers have this facility of path legth correction