Primer Melting Temperature

PCR primer melting temperature (Tm), length.

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Details, formula, and sources

PCR primer melting temperature (Tm), length, and GC content by the Wallace short-oligo rule (<=14 nt) or the basic GC% formula.

Wallace (<=14 nt): Tm = 2(A+T) + 4(G+C). Basic GC% (>14 nt): Tm = 64.9 + 41*(G+C-16.4)/length.

Per Wallace R.B. et al., Nucleic Acids Research 6 (1979), for the short-oligo rule and Marmur & Doty, J Mol Biol 5 (1962) / standard references for the GC% formula, by name.

Free abstracts at pubmed.ncbi.nlm.nih.gov; complements the pcr-master-mix tile.

Estimate. AHJ and licensed professional govern.

Field names used by the API: sequence, method, tm_c, length_nt

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