How does the accuracy and sensitivity of the Qubit quantitation assays using the Qubit fluorometer compare to a microplate reader?
The accuracy and sensitivity of the Qubit quantitation assays are the same as that of a microplate reader. This was a requirement during product development. The detection limits for each Qubit kit can be found on the corresponding product manual, which can be found by searching our website by keyword or catalog number.
Find additional tips, troubleshooting help, and resources within our Nucleic Acid Quantification Support Center.
Can the Qubit kits give an indication of sample quality in nucleic acid samples?
No. The Qubit DNA and RNA kits only quantify the amount of either DNA or RNA in the sample. The Qubit fluorometer cannot take absorbance readings to provide a A260/A280 ratio or detect protein in nucleic acid samples. This can be done with the NanoDrop instrument. If your sample contains protein or other contaminants that can affect the assay, it should be further purified.
If your sample may contain both DNA and RNA, one may use either (or both) the DNA and RNA Qubit kits and compare with samples treated with either RNase or DNase to get an accurate determination of DNA or RNA, respectively.
Can I use the Quant-iT and Qubit Kits with other fluorometers?
All Quant-iT and Qubit kits are compatible with all fluorometers and microplate readers that have the appropriate light sources and filters. You won't have access to the algorithm in the Qubit fluorometer for generating the standard curve provided by the instrument, instead, you must make a few dilutions of the highest standard DNA or RNA (Standard #2) in the Qubit kits to generate a standard curve with multiple data points.
Can I use the original Quant-iT Kits with the Qubit Fluorometer?
No, we do not recommend this. Some of the dyes in the original Quant-iT kits (those NOT listed as “for use with the Qubit fluorometer”) are not compatible with the Qubit Fluorometer. In addition, the new Quant-iT kits (labeled as “for use with the Qubit Fluorometer”) have standards formulated to be compatible with the Qubit fluorometer internal algorithms for the respective assays. The Qubit Fluorometer-compatible kits are also less expensive per assay if you are processing fewer than 20 samples at a time.
I recently purchased a new bag of Qubit Assay Tubes (Cat. No. Q32856) and they look different than the tubes I received before. Are they okay to use?
We have changed the manufacturer of the Qubit Assay Tubes and the new tubes are slightly longer and more opaque than the original tubes. The new tubes have been tested in each of the Qubit instruments, with all of the Qubit assays, and using the fluorescent dyes, fluorescein and Alexa Fluor 647, to validate that there are no changes to the data quality when compared with the original Qubit tubes. The new tubes met or exceeded the current specifications for both the core and extended ranges for each of the Qubit assays, and were able to achieve the same limit of detection (LOD) as the original Qubit tubes for each of the Qubit assays and the fluorescent dyes tested.
Find additional tips, troubleshooting help, and resources within our Protein Assays and Analysis Support Center.
