https://tmcalculator.neb.com/#!/main you can check this... also provides you option to select the enzyme..hope it helps..
Although using Tm° calculators is optimal, when using conventional polymerase (Taq, GoTAQ) and 1.5 mM MgCl2 (GoTAQ has this Mg++ concentration), just subtract 5°C from the lowest Tm° of the primers, i.e. if your primers have Tm of 58°C and 57°C, try the Ta° at 52°C. If primers are properly designed you should get a result when using this approach.
Dear Amira Abou El-Nour
You can calculate the melting temperature of your primer by inserting the oligonucleotide sequence on different software available online, better to use according to your polymerase type and company. Generally the annealing temperature is set by lowering 3-5 °C of the average of primer Tm. Keep in mind that the primer melting temperature should not be too different from each other. If there is such a difference in Tm, then pick the lower one (which has low Tm) and set the annealing temperature 3-5 °C lower than the Tm. If there is still trouble in amplification, you can use gradient PCR or follow touch up gradient amplification method.
Best wishes.
A simple formula that usually works is:
4x (G+C) + 2x (A+T) = Tm
Ta = Tm -5
you can using this a online free software for calculate the annealing temperature to your primer
https://www.thermofisher.com/iq/en/home/brands/thermo-scientific/molecular-biology/molecular-biology-learning-center/molecular-biology-resource-library/thermo-scientific-web-tools/tm-calculator.html
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