I am using the Qubit high-sensitivity kit to quantify low concentration samples of DNA. I am using a new standard curve with each assay, and the Qubit saves the RFU values from these points each time.
I have noticed that the Std 1 RFU values are relatively stable (usually around 39) on one machine, but fluctuate a bit more on another machine located in another lab (41 to 57). Std 2 RFU values are not stable on either machine (from 6000-11,000 or 6000-33,000) on each machine, respectively).
The ambient conditions in the labs for each machine are relatively constant and temperature is not fluctuating more than +/-3°C in each.
Does anyone have an explanation for this huge variation?