NB: 260/280 Measurement
Determination of DNA concentration in 4ward-NA puriSorb DNA extractions
We recommend to determine the DNA concentration after purification with 4ward-NA puriSorb kits:
- Using the fluorescent dye Picogreen or similar
- Comparing the fluorescence intensity of DNA bands of unknown concentration with standards, e.g. in Ethidium bromide stained agarose gels
- With restriction: Absorption measurement at 260 nm (A260) in a spectrophotometer (e.g. NanoDrop®)
Background:
The puriSorb buffer components pass through to the elute. This leads to strong overestimation of the absorption value at 260 nm.
There is no influence on downstream applications (e.g. PCR, qPCR), which is shown during inhibiting experiments.
The overestimation is relatively constant for similar samples (tissue, blood, plant e.g.).
This allows the calculated DNA at A260 to be corrected bb using the "puriSorb Factor".
All calculations of the puriSorb factor are done in correlation with Picogreen.
Example:
Measured DNA concentration after purification of 10 mg cattle muscle tissue : 160 ng/µl
purisorb factor muscle tissue: 0.3
True concentration: 160 ng/µl * 0.3 = 48 ng/µl
Independent of the A260/A280 ratio (< 1.8) the purified DNA is useable in all downstream applications.
There are no products to list in this category.