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Click on the Melting temperature sign (marked as hyperlink) and the Melting temperature settings dialog will be opened.
The melting temperature is calculated as follows. For sequences of length 15 or longer:
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Tm = 64.9 + 41 * (nG + nC - 16.4) / (nA + nT + nG + nC)
For shorter sequences:
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Tm = (nA + nT) * 2 + (nG + nC) * 4
Here "nA", "nT", "nC", "nG" denote the number of the corresponding nucleotide.
nmole/OD260
The amount of DNA or RNA represented in nanomoles per 1 unit of absorbance at 260 nm dissolved in 1 ml cuvette with 1 cm pathlength.
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