Table 2.

Standard primer Tms (°C) calculated for different lengths, Mg2+ concentration, and GC content at 0.8 mM dNTPs and 50 mM monovalent ion concentration without mismatches and with no addition of cosolvents.1

%GCMg2+, mMTm, °C
18 bp20 bp22 bp24 bp
401.052.655.658.060.0
1.554.557.559.961.9
2.055.558.460.862.8
2.556.259.161.563.5
3.056.759.662.064.0
501.056.759.762.164.1
1.558.661.664.066.0
2.059.662.564.966.9
2.560.363.265.667.6
3.060.863.766.168.1
601.060.863.866.268.2
1.562.765.768.170.1
2.063.766.669.071.0
2.564.467.369.771.7
3.064.967.870.272.2