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260/280 nm Validation Reference
For DNA and RNA
Description Standard solution which gives a stable 260/280 nm ratio of 1.8 to 2.0, NIST traceable with UKAS ISO 17025 accredited certificate of calibration
Primary Usage Control the quality of DNA/RNA purity analysis
Useable Range 260 nm and 280 nm
Physical Configuration Far UV quartz cells that have been permanently sealed by heat fusion
NIST Traceability Each set is supplied with a Certificate of Analysis and NIST Traceability
ISO Accredited Accredited by UKAS ISO 17025, ISO Guide34 and ISO 9001

Product Description


View/Download Comprehensive Data Sheet for DNACON Reference

When running DNA or RNA purity analysis on your spectrophotometer, it is important to assure that your instrument is working correctly. Our DNA/RNA validation standard is a permanently sealed quartz cell which contains a stable solution which mimics the 260/280 nm ratio of DNA and RNA. The reference is supplied with a certificate which lists the expected 260/280 nm ratio of the cell and the confidence limit of the ratio. The validation analysis is performed by our ISO 17025 accredited laboratory and is traceable to NIST. The 260/280 ratio has been corrected for any background absorbance at the 330 nm line.


Suggestions for Use

The importance of this reference is that it allows you to validate your work in real time. When measuring unknown samples you can be assured that your instrument is working correctly by reading the validation standard both before and after each run of unknowns. If you are using a spectrophotometer which automatically calculates the 260/280 ratio, then all that you need to do is place the DNA/RNA validation reference in your spectrophotometer and run the instrument's routine for the 260/280 ratio. If the ratio is valid when campared to the certificate, then you can be assured that your instrument is calculating the ratio correctly. In a spectrophotometer without an automatic calculation feature, simply use the DNA/RNA validation reference as you would your other samples to validate your analytical procedure.


Typical uncorrected Absorbance Values:

260 nm 0.765A

280 nm 0.405A

Ratio: 1.89

Interpertation of Results

Consult your spectrophotometer's reference manual for the specification of your instrument's absorbance scale tolerance. This figure will be listed as a plus and minus (+/-) number in absorbance units. Add your instrument's absorbance tolerance to the confidence limit on the certificate supplied with the DNA set for your expected absorbance range. Compare the absorbance values measured on your instrument with the expected values calculated from your instrument manual and the NIST traceable certificate. If the readings are within the expected range for your instrument then your absorbance scale is correct. If not, consult your service techincian and have the instrument evaluated. Quite often if the results of your absorbance measurments are low, it shows that your lamp needs to be replaced.

Quality program

Each time that the analysis is repeated you can compare the new results with the previous results to check for any variance. If your instrument needs service because of a change in absorbance, the historical data will greatly assist the service technician.

How to Order

Catalog Number Description
RM-DNA 260/280 ratio validation reference