Please note that we recently updated our default parameter set to “qPCR” to align with the most commonly used OligoAnalyzer Tool setting.
If you would like to switch the parameters to the previous default of “SpecSheet”, this can be selected from the “Parameter sets” dropdown menu.
Predictions are accurate for oligos from 8 to 60 bases in length, in neutral buffered solutions (pH 7 - 8) with monovalent cation (Na+) concentrations from 1.2 M down to 1.5mM, divalent cation (Mg++) concentrations from 600 mM down to 0.01 mM, and triphosphates (dNTPs) concentrations up to 120% of the divalent cation concentration.
Oligo concentration is assumed to be significantly larger (at least 6x) than concentration of the complementary target, which is true in majority of molecular biology experiments. If this is not a case, concentration of the target cannot be ignored and you should enter in the box,
Oligo Conc = [strand1] – [strand2]/2 when [strand1] ≥ [strand2]
Oligo Conc = ([strand1] + [strand2])/4 when [strand1] = [strand2]
Melting temperature accuracy and models: (Oligo/Template)
DNA/DNA
+/- 1.4ºC (Allawi '97)
LNA/DNA
+/- 2.0ºC (McTigue '04, Owczarzy, 2011)
RNA/DNA
+/- 2.7ºC (Sugimoto '95)
DNA/RNA
+/- 2.7ºC (Sugimoto '95)
RNA/RNA
+/- 1.3ºC (Xia '98)
Divalent cation correction
+/- 0.5ºC (Owczarzy '08)
Triphosphate correction
+/- 0.0ºC (Owczarzy '08)
Monovalent cation correction
+/- 2.0ºC (Owczarzy '04)
Consecutive LNA bases hybridized to a DNA template use a model from Owczarzy '11. In the absence of empirical data, LNA bases on an RNA template assume RNA values, and predictions are therefore less accurate.
Non-consecutive LNA bases hybridized to a DNA template use a model from McTigue '04. Consecutive LNA bases on a DNA template and any LNA bases on an RNA template assume RNA energetic parameters and predictions are therefore less accurate.
Effects of chemical modifications are neglected except when the modification contains a base, e.g., 5-Methyl dC, Internal Fluorescein dT. Energetic effects of these modifications are only approximated.
General Information
Structure
Image
mM
mM
%
oC
Warning: if there is very little or no secondary structure, using a temperature higher than the default may give odd results.
Structures
structure
Image
ΔG (kcal.mole-1)
Tm (oC)
ΔH (kcal.mole-1)
ΔS (cal.K-1mole-1)
Output
*Note dNTP Concentration is not taken into account.
IDT's licensed UNAFold software is available to our customers for the design of oligonucleotide sequences and for use of the resulting oligos purchased from IDT in the purchaser's research applications only. To obtain access to a license to or a copy of the UNAFold software for any other application, including commercial applications, please visit http://mfold.rna.albany.edu/?q=DINAMelt/commercial-license. For the latest information on UNAFold development and additional resources, visit http://mfold.rna.albany.edu/?q=unafold-man-pages
The delta G is calculated by taking into account the longest stretch of complementary bases. These pairs of complementary bases are represented by a solid line. Dotted lines represent additional complementary bases for that dimer structure, but their presence does not impact calculated delta G values. Actual delta G values may vary based on presence of additional complementary bases. The Maximum Delta G value refers to the free energy of the oligo sequence binding to its perfect complement.
For questions regarding the Dimer Analysis contact our Application Support Group 1-800-328-2661 or e-mail Contact Us
Hetero-Dimer Analysis
Primary Sequence:
5'--3'
Secondary Sequence:
5'--3'
The delta G is calculated by taking into account the longest stretch of complementary bases. These pairs of complementary bases are represented by a solid line. Dotted lines represent additional complementary bases for that dimer structure, but their presence does not impact calculated delta G values. Actual delta G values may vary based on presence of additional complementary bases. The Maximum Delta G value refers to the free energy of the oligo sequence binding to its perfect complement.
For questions regarding the Dimer Analysis contact our Application Support Group 1-800-328-2661 or Contact Us
Exact and Single Base Mismatch DNA Thermodynamics
Primary Sequence: 5' to 3'; Target Sequence: 3' to 5'